IS-IS Working Group                                         S. Litkowski
Internet-Draft                                                    Orange
Intended status: Standards Track                                D. Yeung
Expires: February 10, May 30, 2019                                        Arrcus, Inc
                                                               A. Lindem
                                                           Cisco Systems
                                                                J. Zhang
                                                        Juniper Networks
                                                               L. Lhotka
                                                                  CZ.NIC
                                                         August 09,
                                                       November 26, 2018

                   YANG Data Model for IS-IS protocol
                    draft-ietf-isis-yang-isis-cfg-24
                    draft-ietf-isis-yang-isis-cfg-25

Abstract

   This document defines a YANG data model that can be used to configure
   and manage IS-IS protocol on network elements.

Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. BCP
   14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
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   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on February 10, May 30, 2019.

Copyright Notice

   Copyright (c) 2018 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
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   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
     1.1.  Tree diagram  . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Design of the Data Model  . . . . . . . . . . . . . . . . . .   4   3
     2.1.  IS-IS Configuration . . . . . . . . . . . . . . . . . . .  10   9
     2.2.  Multitopology Parameters  . . . . . . . . . . . . . . . .  10   9
     2.3.  Per-Level Parameters  . . . . . . . . . . . . . . . . . .  10
     2.4.  Per-Interface Parameters  . . . . . . . . . . . . . . . .  12  11
     2.5.  Authentication Parameters . . . . . . . . . . . . . . . .  23  17
     2.6.  IGP/LDP synchronization . . . . . . . . . . . . . . . . .  23  17
     2.7.  ISO parameters  . . . . . . . . . . . . . . . . . . . . .  24  17
     2.8.  IP FRR  . . . . . . . . . . . . . . . . . . . . . . . . .  24  18
     2.9.  Operational States  . . . . . . . . . . . . . . . . . . .  24  18
   3.  RPC Operations  . . . . . . . . . . . . . . . . . . . . . . .  25  19
   4.  Notifications . . . . . . . . . . . . . . . . . . . . . . . .  25  19
   5.  Interaction with Other YANG Modules . . . . . . . . . . . . .  26  20
   6.  IS-IS YANG Module . . . . . . . . . . . . . . . . . . . . . .  27  21
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .  95 100
   8.  Contributors  . . . . . . . . . . . . . . . . . . . . . . . .  96 101
   9.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  96 101
   10. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  96 101
   11. Change log for ietf-isis YANG module  . . . . . . . . . . . .  96 101
     11.1.  From version -24 to version -25  . . . . . . . . . . . . 101
     11.2.  From version -22 to version -24  . . . . . . . . . . . .  96
     11.2. 102
     11.3.  From version -21 to version -22  . . . . . . . . . . . .  96
     11.3. 102
     11.4.  From version -20 to version -21  . . . . . . . . . . . .  96
     11.4. 103
     11.5.  From version -19 to version -20  . . . . . . . . . . . .  97
     11.5. 103
     11.6.  From version -18 to version -19  . . . . . . . . . . . .  97
     11.6. 103
     11.7.  From version -17 to version -18  . . . . . . . . . . . .  97
     11.7. 103
     11.8.  From version -16 to version -17  . . . . . . . . . . . .  97
     11.8. 103
     11.9.  From version -15 to version -16  . . . . . . . . . . . .  97
     11.9. 103
     11.10. From version -14 to version -15  . . . . . . . . . . . .  97
     11.10. 104
     11.11. From version -13 to version -14  . . . . . . . . . . . .  98
     11.11. 104
     11.12. From version -12 to version -13  . . . . . . . . . . . .  98
     11.12. 104
     11.13. From version -09 to version -12  . . . . . . . . . . . .  98
     11.13. 104
     11.14. From version -08 to version -09  . . . . . . . . . . . .  98
     11.14. 105
     11.15. From version -07 to version -08  . . . . . . . . . . . .  99
     11.15. 105
     11.16. From version -05 to version -07  . . . . . . . . . . . .  99
     11.16. 105
     11.17. From version -03 to version -05  . . . . . . . . . . . .  99
     11.17. 105
     11.18. From version -02 to version -03  . . . . . . . . . . . .  99
     11.18. 106
     11.19. From version -01 to version -02  . . . . . . . . . . . . 100
     11.19. 106
     11.20. From version -00 to version -01  . . . . . . . . . . . . 100 106
   12. References  . . . . . . . . . . . . . . . . . . . . . . . . . 107
     12.1.  Normative References . . . . . . . . . . . . . . . . . . 107
     12.2.  Informative References . . 101 . . . . . . . . . . . . . . . 109
   Appendix A.  Example of IS-IS configuration in XML  . . . . . . . 102 109
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . . 104 112

1.  Introduction

   This document defines a YANG ([RFC7950]) data model for IS-IS routing
   protocol.

   The data model covers configuration of an IS-IS routing protocol
   instance as well as operational states.

1.1.  Tree diagram

   A simplified graphical tree representation of the data model is presented in
   Section 2.

   The meaning of  Tree diagrams used in this document follow the symbols notation
   defined in these diagrams [RFC8340].

   The module is designed as follows:

   o  Brackets "[" and "]" enclose list keys.

   o  Curly braces "{" and "}" contain names of optional features that
      make the corresponding node conditional.

   o  Abbreviations before data node names: "rw" means configuration
      (read-write), and "ro" state data (read-only).

   o  Symbols after data node names: "?" means an optional node and "*"
      denotes a "list" or "leaf-list".

   o  Parentheses enclose choice and case nodes, and case nodes are also
      marked with a colon (":").

   o  Ellipsis ("...") stands for contents of subtrees that are not
      shown. per NMDA (Network Management Datastore
   Architecture) [RFC8342].

2.  Design of the Data Model

   The IS-IS YANG module augments the "control-plane-protocol" list in
   ietf-routing module (defined in [RFC8349]) with specific IS-IS
   parameters.

   The module is designed as per NMDA (Network Management Datastore
   Architecture).

   The figure below describes the overall structure of the isis YANG
   module:

module: ietf-isis
  augment /rt:routing/rt:ribs/rt:rib/rt:routes/rt:route:
    +--ro metric?       uint32
    +--ro tag*          uint64
    +--ro route-type?   enumeration
  augment /if:interfaces/if:interface:
    +--rw clns-mtu?   uint16
  augment /rt:routing/rt:control-plane-protocols/
      |      rt:control-plane-protocol:
/rt:routing/rt:control-plane-protocols/rt:control-plane-protocol:

    +--rw isis
       +--rw enable?                   boolean {admin-control}?
       +--rw level-type?               level
       +--rw system-id?                system-id
       +--rw maximum-area-addresses?   uint8 {maximum-area-addresses}?
       +--rw area-address*             area-address
       +--rw mpls
         |  +--rw te-rid {te-rid}?
         |  |     ...
         |  +--rw ldp
         |        ...
         +--rw auto-cost {auto-cost}?
         |  +--rw reference-bandwidth?   uint32
         |  +--rw enable?                boolean
         +--rw lsp-mtu?                  uint16
       +--rw lsp-lifetime?             uint16
       +--rw lsp-refresh?
         |              rt-types:timer-value-seconds16
{lsp-refresh}?
       +--rw poi-tlv?                  boolean {poi-tlv}?
       +--rw graceful-restart {graceful-restart}?
       |  +--rw enable?             boolean
       |  +--rw restart-interval?   rt-types:timer-value-seconds16
       |  +--rw helper-enable?      boolean
       +--rw nsr {nsr}?
       |  +--rw enable?   boolean
       +--rw node-tags {node-tag}?
       |  +--rw node-tag* [tag]
       |        ...
       +--rw authentication
         |  +--rw (authentication-type)?
         |  |     ...
         |  +--rw level-1
         |  |     ...
         |  +--rw level-2
         |        ...
         +--rw metric-type
       |  +--rw value?     enumeration
       |  +--rw level-1
       |  |     ...
       |  +--rw level-2
       |        ...
       +--rw default-metric
       |  +--rw value?     wide-metric
       |  +--rw level-1
       |  |     ...
       |  +--rw level-2
       |        ...
       +--rw afs {nlpid-control}? auto-cost {auto-cost}?
       |  +--rw af* [af] enable?                boolean
       |        ...  +--rw preference reference-bandwidth?   uint32
       +--rw authentication
       |  +--rw (granularity)? (authentication-type)?
       |  |     ...
         +--rw overload
       |  +--rw status?   boolean
         +--rw overload-max-metric {overload-max-metric}? level-1
       |  +--rw timeout?   rt-types:timer-value-seconds16
         +--rw fast-reroute {fast-reroute}?  |     ...
       |  +--rw lfa {lfa}? level-2
       |  +--ro protected-routes        ...
       +--rw address-families {nlpid-control}?
       |  +--rw address-family-list* [address-family]
       |        ...
       +--rw mpls
       |  +--ro unprotected-routes  +--rw te-rid {te-rid}?
       |  |     ...
       |  +--ro protection-statistics* [frr-protection-method]  +--rw ldp
       |        ...
       +--rw spf-control
       |  +--rw paths?            uint16 {max-ecmp}?
       |  +--rw ietf-spf-delay {ietf-spf-delay}?
       |        ...
       +--rw topologies {multi-topology}? fast-reroute {fast-reroute}?
       |  +--rw topology* [name] lfa {lfa}?
       +--rw preference
       |  +--rw (granularity)?
       |        ...
       +--rw interfaces overload
       |  +--rw interface* [name] status?   boolean
       +--rw overload-max-metric {overload-max-metric}?
       |        ...  +--rw timeout?   rt-types:timer-value-seconds16
       +--ro spf-log
       |  +--ro event* [id]
       |        ...
       +--ro lsp-log
       |  +--ro event* [id]
       |        ...
       +--ro hostnames
       |  +--ro hostname* [system-id]
       |        ...
       +--ro database
       |  +--ro level-db* [level]
       |        ...
       +--ro local-rib
       |  +--ro route* [prefix]
       |        ...
       +--ro system-counters
       |  +--ro level* [level]
       |        ...
       +--ro protected-routes
       |  +--ro address-family-stats* [address-family prefix alternate]
       |        ...
       +--ro unprotected-routes
       |  +--ro address-family-stats* [address-family prefix]
       |        ...
       +--ro protection-statistics* [frr-protection-method]
       |  +--ro frr-protection-method    string
       |  +--ro address-family-stats* [address-family]
       |        ...
       +--rw topologies {multi-topology}?
       |  +--rw topology* [name]
       |        ...
       +--rw interfaces
          +--rw interface* [name]
                ...

  rpcs:
    +---x clear-adjacency
    |  +---w input
    |     +---w routing-protocol-instance-name    instance-state-ref    ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |     +---w level?                            level
    |     +---w interface?                        string                        if:interface-ref
    +---x clear-database
       +---w input
          +---w routing-protocol-instance-name    instance-state-ref    ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
          +---w level?                            level

  notifications:
    +---n database-overload
    |  +--ro routing-instance?        string
      |  +--ro routing-protocol-name?   string   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro overload?                enumeration
    +---n lsp-too-large
    |  +--ro routing-instance?        string
      |  +--ro routing-protocol-name?   string   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string          if:interface-ref
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro pdu-size?                uint32
    |  +--ro lsp-id?                  lsp-id
    +---n if-state-change
    |  +--ro routing-instance?        string
      |  +--ro routing-protocol-name?   string   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string          if:interface-ref
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro state?                   if-state-type
    +---n corrupted-lsp-detected
    |  +--ro routing-instance?        string
      |  +--ro routing-protocol-name?   string   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro lsp-id?                  lsp-id
    +---n attempt-to-exceed-max-sequence
    |  +--ro routing-instance?        string
      |  +--ro routing-protocol-name?   string   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro lsp-id?                  lsp-id
    +---n id-len-mismatch
    |  +--ro routing-instance?        string
      |  +--ro routing-protocol-name?   string   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string          if:interface-ref
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro pdu-field-len?           uint8
    |  +--ro raw-pdu?                 binary
    +---n max-area-addresses-mismatch
    |  +--ro routing-instance?        string
      |  +--ro routing-protocol-name?   string   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string          if:interface-ref
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro max-area-addresses?      uint8
    |  +--ro raw-pdu?                 binary
    +---n own-lsp-purge
    |  +--ro routing-instance?        string
      |  +--ro routing-protocol-name?   string   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string          if:interface-ref
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro lsp-id?                  lsp-id
    +---n sequence-number-skipped
    |  +--ro routing-instance?        string
      |  +--ro routing-protocol-name?   string   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string          if:interface-ref
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro lsp-id?                  lsp-id
    +---n authentication-type-failure
    |  +--ro routing-instance?        string
      |  +--ro routing-protocol-name?   string   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string          if:interface-ref
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro raw-pdu?                 binary
    +---n authentication-failure
    |  +--ro routing-instance?        string
      |  +--ro routing-protocol-name?   string   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string          if:interface-ref
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro raw-pdu?                 binary
    +---n version-skew
    |  +--ro routing-instance?        string
      |  +--ro routing-protocol-name?   string   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string          if:interface-ref
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro protocol-version?        uint8
    |  +--ro raw-pdu?                 binary
    +---n area-mismatch
    |  +--ro routing-instance?        string
      |  +--ro routing-protocol-name?   string   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string          if:interface-ref
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro raw-pdu?                 binary
    +---n rejected-adjacency
    |  +--ro routing-instance?        string
      |  +--ro routing-protocol-name?   string   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string          if:interface-ref
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro raw-pdu?                 binary
    |  +--ro reason?                  string
    +---n protocols-supported-mismatch
    |  +--ro routing-instance?        string
      |  +--ro routing-protocol-name?   string   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string          if:interface-ref
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro raw-pdu?                 binary
    |  +--ro protocols*               uint8
    +---n lsp-error-detected
    |  +--ro routing-instance?        string
      |  +--ro routing-protocol-name?   string   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string          if:interface-ref
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro lsp-id?                  lsp-id
    |  +--ro raw-pdu?                 binary
    |  +--ro error-offset?            uint32
    |  +--ro tlv-type?                uint8
    +---n adjacency-state-change
    |  +--ro routing-instance?        string
      |  +--ro routing-protocol-name?   string routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string          if:interface-ref
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro neighbor?                string
    |  +--ro neighbor-system-id?      system-id
    |  +--ro state?                   adj-state-type
    |  +--ro reason?                  string
    +---n lsp-received
    |  +--ro routing-instance?        string
      |  +--ro routing-protocol-name?   string   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string          if:interface-ref
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro lsp-id?                  lsp-id
    |  +--ro sequence?                uint32
    |  +--ro received-timestamp?      yang:timestamp
    |  +--ro neighbor-system-id?      system-id
    +---n lsp-generation
       +--ro routing-instance?        string
         +--ro routing-protocol-name?   string   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
       +--ro isis-level?              level
       +--ro lsp-id?                  lsp-id
       +--ro sequence?                uint32
       +--ro send-timestamp?          yang:timestamp

2.1.  IS-IS Configuration

   The IS-IS configuration container is divided in:

   o  Global parameters.

   o  Per interface configuration (see Section 2.4).

   Additional modules may be created this to support any additional
   parameters.  These additional modules should MUST augment the ietf-isis
   module.

   The model implements features, thus some of the configuration
   statement becomes optional.  As an example, the ability to control
   the administrative state of a particular IS-IS instance is optional.
   By advertising the feature "admin-control", a device communicates to
   the client that it supports the ability to shutdown a particular IS-
   IS instance.

   The global configuration contains usual IS-IS parameters such as lsp-
   mtu, lsp-lifetime, lsp-refresh, default-metric...

2.2.  Multitopology Parameters

   The model supports multitopology (MT) IS-IS as defined in [RFC5120].

   The "topologies" container is used to enable support of MT
   extensions.

   The "name" used in the topology list should refer to an existing RIB
   of the device.

   Some specific parameters could be defined on a per topology basis
   both at global level and at interface level: for example, an
   interface metric can be defined per topology.

   Multiple address families (like IPv4 or IPv6) can also be activated
   within the default topology.  This can be achieved using the "afs"
   container (requiring "nlpid-control" feature to be advertised).

2.3.  Per-Level Parameters

   Some parameters allow a per level configuration.  In this case, the
   parameter is modeled as a container with three configuration
   locations:

   o  a top level container: corresponds to level-1-2, so the
      configuration applies to both levels.

   o  a level-1 container: corresponds to level-1 specific parameters.

   o  a level-2 container: corresponds to level-2 specific parameters.

               +--rw priority
               |  +--rw value?     uint8
               |  +--rw level-1
               |  |  +--rw value?   uint8
               |  +--rw level-2
               |     +--rw value?   uint8

   Example:

           <priority>
               <value>250</value>
               <level-1>
                   <value>100</value>
               </level-1>
               <level-2>
                   <value>200</value>
               </level-2>
           </priority>

   An implementation SHOULD prefer a level specific parameter over a
   level-all parameter.  As example, if the priority is 100 for the
   level-1, 200 for the level-2 and 250 for the top level configuration,
   the implementation should use 100 for the level-1 and 200 for the
   level-2.

   Some parameters like "overload bit" and "route preference" are not
   modeled to support a per level configuration.  If an implementation
   supports per level configuration for such parameter, this
   implementation SHOULD augment the current model by adding both
   level-1 and level-2 containers and SHOULD reuse existing
   configuration groupings.

   Example of augmentation:

   augment "/rt:routing/" +
           "rt:control-plane-protocols/rt:control-plane-protocol"+
           "/isis:isis/isis:overload" {
           when "rt:type = 'isis:isis'" {
             description
              "This augment IS-IS routing protocol when used";
           }
           description
             "This augments IS-IS overload configuration
              with per level configuration.";

           container level-1 {
             uses isis:overload-global-cfg;
             description
               "Level 1 configuration.";
           }
           container level-2 {
             uses isis:overload-global-cfg;
             description
               "Level 2 configuration.";
           }
   }

   If an implementation does not support per level configuration for a
   parameter modeled with per level configuration, the implementation
   SHOULD advertise a deviation to announce the non support of the
   level-1 and level-2 containers.

   Finally, if an implementation supports per level configuration but
   does not support the level-1-2 configuration, it SHOULD also
   advertise a deviation.

2.4.  Per-Interface Parameters

   The per-interface section of the IS-IS instance describes the
   interface specific parameters.

   The interface is modeled as a reference to an existing interface
   defined in the "ietf-interfaces" YANG model. model ([RFC8343].

   Each interface has some interface-specific parameters that may have a
   different per level value as described in previous section.  An
   interface-specific parameter always override an IS-IS global
   parameter.

   Some parameters like hello-padding are defined as containers to allow
   easy extension by vendor specific modules.

       +--rw interfaces
       |
          +--rw interface* [name]
       |
             +--rw name                       if:interface-ref
       |
             +--rw level-type?                level
       |
             +--rw lsp-pacing-interval?
       |     |
rt-types:timer-value-milliseconds
       |
             +--rw lsp-retransmit-interval?
       |     |
rt-types:timer-value-seconds16
       |
             +--rw passive?                   boolean
       |
             +--rw csnp-interval?
       |     |
rt-types:timer-value-seconds16
       |
             +--rw hello-padding
             |     |  +--rw enable?   boolean
       |
             +--rw mesh-group-enable?         mesh-group-state
       |
             +--rw mesh-group?                uint8
       |
             +--rw interface-type?            interface-type
       |
             +--rw enable?                    boolean {admin-control}?
       |
             +--rw tag*                       uint32 {prefix-tag}?
       |
             +--rw tag64*                     uint64 {prefix-tag64}?
       |
             +--rw node-flag?                 boolean {node-flag}?
       |
             +--rw hello-authentication
             |     |  +--rw (authentication-type)?
             |  |  |  +--:(key-chain) {key-chain}?
             |  |  |  |  +--rw key-chain?          key-chain:key-chain-ref
             |  |  |  +--:(password)
             |  |  |     +--rw key?                string
             |  |  |     +--rw crypto-algorithm?   identityref
             |     |  +--rw level-1
             |  |  |  +--rw (authentication-type)?
             |  |  |     +--:(key-chain) {key-chain}?
             |  |     |     |  +--rw key-chain?
key-chain:key-chain-ref
             |  |  |     +--:(password)
             |  |  |        +--rw key?                string
             |  |  |        +--rw crypto-algorithm?   identityref
             |     |  +--rw level-2
             |     |     +--rw (authentication-type)?
             |     |        +--:(key-chain) {key-chain}?
             |        |        |  +--rw key-chain?
key-chain:key-chain-ref
             |     |        +--:(password)
             |     |           +--rw key?                string
             |     |           +--rw crypto-algorithm?   identityref
       |
             +--rw hello-interval
             |     |  +--rw value?     rt-types:timer-value-seconds16
             |     |  +--rw level-1
             |  |  |  +--rw value?   rt-types:timer-value-seconds16
             |     |  +--rw level-2
             |     |     +--rw value?   rt-types:timer-value-seconds16
       |
             +--rw hello-multiplier
             |     |  +--rw value?     uint16
             |     |  +--rw level-1
             |  |  |  +--rw value?   uint16
             |     |  +--rw level-2
             |     |     +--rw value?   uint16
       |
             +--rw priority
             |     |  +--rw value?     uint8
             |     |  +--rw level-1
             |  |  |  +--rw value?   uint8
             |     |  +--rw level-2
             |     |     +--rw value?   uint8
       |
             +--rw metric
             |     |  +--rw value?     wide-metric
             |     |  +--rw level-1
             |  |  |  +--rw value?   wide-metric
             |     |  +--rw level-2
             |     |     +--rw value?   wide-metric
       |
             +--rw bfd {bfd}?
             |     |  +--rw enable?                           boolean
             |     |  +--rw local-multiplier?                 multiplier
             |     |  +--rw (interval-config-type)?
             |     |     +--:(tx-rx-intervals)
             |     |     |  +--rw desired-min-tx-interval?    uint32
             |     |     |  +--rw required-min-rx-interval?   uint32
             |     |     +--:(single-interval) {single-minimum-interval}?
             |     |        +--rw min-interval?               uint32
       |
             +--rw afs address-families {nlpid-control}?
             |     |  +--rw af* [af]
       | address-family-list* [address-family]
             |     +--rw af address-family    iana-rt-types:address-family
       |
             +--rw mpls
             |     |  +--rw ldp
             |     |     +--rw igp-sync?   boolean {ldp-igp-sync}?
       |
             +--rw fast-reroute {fast-reroute}?
             |     |  +--rw lfa {lfa}?
             |     |     +--rw candidate-disabled? candidate-enable?   boolean
             |     |     +--rw enable?             boolean
             |     |     +--rw remote-lfa {remote-lfa}?
             |     |     |  +--rw enable?   boolean
             |     |     +--rw level-1
             |     |     |  +--rw candidate-disabled? candidate-enable?   boolean
             |     |     |  +--rw enable?             boolean
             |     |     |  +--rw remote-lfa {remote-lfa}?
             |     |     |     +--rw enable?   boolean
             |     |     +--rw level-2
             |     |        +--rw candidate-disabled? candidate-enable?   boolean
             |     |        +--rw enable?             boolean
             |     |        +--rw remote-lfa {remote-lfa}?
             |     |           +--rw enable?   boolean
       |
             +--rw topologies {multi-topology}?
       |     |
                +--rw topology* [name]
       |     |
                   +--rw name
       |     |      ->
../../../../../../../../rt:ribs/rib/name
       |     |
                   +--rw metric
       |     |
                      +--rw value?     wide-metric
       |     |
                      +--rw level-1
                      |     |        |  +--rw value?   wide-metric
       |     |
                      +--rw level-2
       |     |
                         +--rw value?   wide-metric

  rpcs:
    +---x clear-adjacency
    |     +--ro adjacencies  +---w input
    |     +---w routing-protocol-instance-name    ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro adjacency* []     +---w level?                            level
    |     +---w interface?                        if:interface-ref
    +---x clear-database
       +---w input
          +---w routing-protocol-instance-name    ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
          +---w level?                            level

  notifications:
    +---n database-overload
    |  +--ro routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro neighbor-sys-type? isis-level?              level
    |  +--ro overload?                enumeration
    +---n lsp-too-large
    |  +--ro neighbor-sysid?                 system-id routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro neighbor-extended-circuit-id? interface-name?          if:interface-ref
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro pdu-size?                uint32
    |  +--ro neighbor-snpa?                  snpa lsp-id?                  lsp-id
    +---n if-state-change
    |  +--ro routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro usage? isis-level?              level
    |     |  +--ro hold-timer?
       |     |             rt-types:timer-value-seconds16
       | interface-name?          if:interface-ref
    |  +--ro neighbor-priority?              uint8
       | interface-level?         level
    |  +--ro lastuptime?                     yang:timestamp
       | extended-circuit-id?     extended-circuit-id
    |  +--ro state?                          adj-state-type                   if-state-type
    +---n corrupted-lsp-detected
    |  +--ro event-counters
       | routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro adjacency-changes?             uint32
       | isis-level?              level
    |  +--ro adjacency-number?              uint32
       | lsp-id?                  lsp-id
    +---n attempt-to-exceed-max-sequence
    |  +--ro init-fails?                    uint32
       | routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro adjacency-rejects?             uint32
       | isis-level?              level
    |  +--ro id-len-mismatch?               uint32
       | lsp-id?                  lsp-id
    +---n id-len-mismatch
    |  +--ro max-area-addresses-mismatch?   uint32
       | routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro authentication-type-fails?     uint32 isis-level?              level
    |  +--ro interface-name?          if:interface-ref
    |  +--ro authentication-fails?          uint32 interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro lan-dis-changes?               uint32 pdu-field-len?           uint8
    |  +--ro packet-counters raw-pdu?                 binary
    +---n max-area-addresses-mismatch
    |  +--ro level* [level] routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level      level-number
    |  +--ro iih
       | interface-name?          if:interface-ref
    |  +--ro in?    uint32
       | interface-level?         level
    |  +--ro out?   uint32 extended-circuit-id?     extended-circuit-id
    |  +--ro ish
       | max-area-addresses?      uint8
    |  +--ro in?    uint32
       | raw-pdu?                 binary
    +---n own-lsp-purge
    |  +--ro out?   uint32 routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro esh
       | isis-level?              level
    |  +--ro in?    uint32
       | interface-name?          if:interface-ref
    |  +--ro out?   uint32 interface-level?         level
    |  +--ro lsp
       | extended-circuit-id?     extended-circuit-id
    |  +--ro in?    uint32
       | lsp-id?                  lsp-id
    +---n sequence-number-skipped
    |  +--ro out?   uint32 routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro psnp
       | isis-level?              level
    |  +--ro in?    uint32
       | interface-name?          if:interface-ref
    |  +--ro out?   uint32 interface-level?         level
    |  +--ro csnp extended-circuit-id?     extended-circuit-id
    |  +--ro lsp-id?                  lsp-id
    +---n authentication-type-failure
    |  +--ro in?    uint32 routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level
    |  +--ro out?   uint32 interface-name?          if:interface-ref
    |  +--ro unknown interface-level?         level
    |  +--ro in?    uint32 extended-circuit-id?     extended-circuit-id
    |  +--ro out?   uint32 raw-pdu?                 binary
    +---n authentication-failure
    |  +--ro spf-log routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro event* [id] isis-level?              level
    |  +--ro id                    uint32 interface-name?          if:interface-ref
    |  +--ro spf-type?             enumeration interface-level?         level
    |  +--ro level?                level-number extended-circuit-id?     extended-circuit-id
    |  +--ro schedule-timestamp?   yang:timestamp raw-pdu?                 binary
    +---n version-skew
    |  +--ro start-timestamp?      yang:timestamp routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro end-timestamp?        yang:timestamp isis-level?              level
    |  +--ro trigger-lsp* [lsp] interface-name?          if:interface-ref
    |  +--ro lsp         lsp-id interface-level?         level
    |  +--ro sequence?   uint32 extended-circuit-id?     extended-circuit-id
    |  +--ro lsp-log protocol-version?        uint8
    |  +--ro event* [id] raw-pdu?                 binary
    +---n area-mismatch
    |  +--ro id                    uint32 routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro level?                level-number isis-level?              level
    |  +--ro lsp interface-name?          if:interface-ref
    |  +--ro interface-level?         level
    |  +--ro lsp?        lsp-id extended-circuit-id?     extended-circuit-id
    |  +--ro raw-pdu?                 binary
    +---n rejected-adjacency
    |  +--ro sequence?   uint32 routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro received-timestamp?   yang:timestamp isis-level?              level
    |  +--ro change?               identityref interface-name?          if:interface-ref
    |  +--ro hostnames interface-level?         level
    |  +--ro hostname* [system-id] extended-circuit-id?     extended-circuit-id
    |  +--ro system-id    system-id raw-pdu?                 binary
    |  +--ro hostname? reason?                  string
       +--ro database
    +---n protocols-supported-mismatch
    |  +--ro level-db* [level] routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro isis-level?              level    level-number
    |  +--ro lsp* [lsp-id] interface-name?          if:interface-ref
    |  +--ro decoded-completed?               boolean interface-level?         level
    |  +--ro raw-data?                        yang:hex-string extended-circuit-id?     extended-circuit-id
    |  +--ro lsp-id                           lsp-id raw-pdu?                 binary
    |  +--ro checksum?                        uint16 protocols*               uint8
    +---n lsp-error-detected
    |  +--ro remaining-lifetime?              uint16 routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro sequence?                        uint32 isis-level?              level
    |  +--ro attributes?                      bits interface-name?          if:interface-ref
    |  +--ro ipv4-addresses*                  inet:ipv4-address interface-level?         level
    |  +--ro ipv6-addresses*                  inet:ipv6-address extended-circuit-id?     extended-circuit-id
    |  +--ro ipv4-te-routerid?                inet:ipv4-address lsp-id?                  lsp-id
    |  +--ro ipv6-te-routerid?                inet:ipv6-address raw-pdu?                 binary
    |  +--ro protocol-supported*              uint8 error-offset?            uint32
    |  +--ro dynamic-hostname?                string
       |        +--ro authentication
       |        |  +--ro authentication-type?   string
       |        |  +--ro authentication-key?    string
       |        +--ro mt-entries
       |        |  +--ro topology* []
       |        |     +--ro MT-ID?        uint16
       |        |     +--ro attributes?   bits
       |        +--ro router-capabilities* []
       |        |  +--ro flags?       bits
       | tlv-type?                uint8
    +---n adjacency-state-change
    |  +--ro node-tags {node-tag}?
       |        | routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro node-tag* []
       |        | isis-level?              level
    |  +--ro tag?   uint32
       | interface-name?          if:interface-ref
    |  +--ro binary?      binary interface-level?         level
    |  +--ro is-neighbor
       | extended-circuit-id?     extended-circuit-id
    |  +--ro neighbor* []
       | neighbor?                string
    |  +--ro neighbor-id? neighbor-system-id?      system-id
    |        |  +--ro i-e?              boolean
       |        |     +--ro default-metric?   std-metric
       |        |     +--ro delay-metric
       |        |     |  +--ro metric?      std-metric
       |        | state?                   adj-state-type
    |  +--ro supported?   boolean
       | reason?                  string
    +---n lsp-received
    |  +--ro expense-metric
       |        | routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
    |  +--ro metric?      std-metric
       |        | isis-level?              level
    |  +--ro supported?   boolean
       | interface-name?          if:interface-ref
    |  +--ro error-metric
       | interface-level?         level
    |  +--ro metric?      std-metric
       | extended-circuit-id?     extended-circuit-id
    |  +--ro supported?   boolean lsp-id?                  lsp-id
    |  +--ro extended-is-neighbor
       | sequence?                uint32
    |  +--ro neighbor* []
       | received-timestamp?      yang:timestamp
    |  +--ro neighbor-id? neighbor-system-id?      system-id
       |        |     +--ro metric?        wide-metric
       |        +--ro ipv4-internal-reachability
       |        |  +--ro prefixes* []
       |        |     +--ro up-down?          boolean
       |        |     +--ro i-e?              boolean
       |        |     +--ro ip-prefix?        inet:ipv4-address
       |        |     +--ro prefix-len?       uint8
       |        |     +--ro default-metric?   std-metric
       |        |     +--ro delay-metric
       |        |     |  +--ro metric?      std-metric
       |        |     |  +--ro supported?   boolean
       |        |     +--ro expense-metric
       |        |     |  +--ro metric?      std-metric
       |        |     |  +--ro supported?   boolean
       |        |     +--ro error-metric
       |        |        +--ro metric?      std-metric
       |        |        +--ro supported?   boolean
       |        +--ro ipv4-external-reachability
       |        |  +--ro prefixes* []
       |        |     +--ro up-down?          boolean
       |        |     +--ro i-e?              boolean
       |        |     +--ro ip-prefix?        inet:ipv4-address
       |        |     +--ro prefix-len?       uint8
       |        |     +--ro default-metric?   std-metric
       |        |     +--ro delay-metric
       |        |     |
    +---n lsp-generation
       +--ro metric?      std-metric
       |        |     | routing-protocol-name?   ->
/rt:routing/control-plane-protocols/control-plane-protocol/name
       +--ro supported?   boolean
       |        | isis-level?              level
       +--ro expense-metric
       |        |     | lsp-id?                  lsp-id
       +--ro metric?      std-metric
       |        |     |  +--ro supported?   boolean
       |        |     +--ro error-metric
       |        |        +--ro metric?      std-metric
       |        |        +--ro supported?   boolean
       |        +--ro extended-ipv4-reachability
       |        |  +--ro prefixes* []
       |        |     +--ro up-down?                 boolean
       |        |     +--ro ip-prefix?               inet:ipv4-address
       |        |     +--ro prefix-len?              uint8
       |        |     +--ro metric?                  wide-metric
       |        |     +--ro tag*                     uint32
       |        |     +--ro tag64*                   uint64
       |        |     +--ro external-prefix-flag?    boolean
       |        |     +--ro readvertisement-flag?    boolean
       |        |     +--ro node-flag?               boolean
       |        |     +--ro ipv4-source-router-id?   inet:ipv4-address
       |        |     +--ro ipv6-source-router-id?   inet:ipv6-address
       |        +--ro mt-is-neighbor
       |        |  +--ro neighbor* []
       |        |     +--ro mt-id?         uint16
       |        |     +--ro neighbor-id?   system-id
       |        |     +--ro metric?        wide-metric
       |        +--ro mt-extended-ipv4-reachability
       |        |  +--ro prefixes* []
       |        |     +--ro mt-id?                   uint16
       |        |     +--ro up-down?                 boolean
       |        |     +--ro ip-prefix?               inet:ipv4-address
       |        |     +--ro prefix-len?              uint8
       |        |     +--ro metric?                  wide-metric
       |        |     +--ro tag*                     uint32
       |        |     +--ro tag64*                   uint64
       |        |     +--ro external-prefix-flag?    boolean
       |        |     +--ro readvertisement-flag?    boolean
       |        |     +--ro node-flag?               boolean
       |        |     +--ro ipv4-source-router-id?   inet:ipv4-address
       |        |     +--ro ipv6-source-router-id?   inet:ipv6-address
       |        +--ro mt-ipv6-reachability
       |        |  +--ro prefixes* []
       |        |     +--ro MT-ID?                   uint16
       |        |     +--ro up-down?                 boolean
       |        |     +--ro ip-prefix?               inet:ipv6-address
       |        |     +--ro prefix-len?              uint8
       |        |     +--ro metric?                  wide-metric
       |        |     +--ro tag*                     uint32
       |        |     +--ro tag64*                   uint64
       |        |     +--ro external-prefix-flag?    boolean
       |        |     +--ro readvertisement-flag?    boolean
       |        |     +--ro node-flag?               boolean
       |        |     +--ro ipv4-source-router-id?   inet:ipv4-address
       |        |     +--ro ipv6-source-router-id?   inet:ipv6-address
       |        +--ro ipv6-reachability
       |           +--ro prefixes* []
       |              +--ro up-down?                 boolean
       |              +--ro ip-prefix?               inet:ipv6-address
       |              +--ro prefix-len?              uint8
       |              +--ro metric?                  wide-metric
       |              +--ro tag*                     uint32
       |              +--ro tag64*                   uint64
       |              +--ro external-prefix-flag?    boolean
       |              +--ro readvertisement-flag?    boolean
       |              +--ro node-flag?               boolean
       |              +--ro ipv4-source-router-id?   inet:ipv4-address
       |              +--ro ipv6-source-router-id?   inet:ipv6-address
       +--ro local-rib
       |  +--ro route* [prefix]
       |     +--ro prefix       inet:ip-prefix
       |     +--ro next-hops
       |     |  +--ro next-hop* [next-hop]
       |     |     +--ro outgoing-interface?   if:interface-ref
       |     |     +--ro next-hop              inet:ip-address
       |     +--ro metric?      uint32
       |     +--ro level?       level-number
       |     +--ro route-tag?   uint32
       +--ro system-counters
          +--ro level* [level]
             +--ro level                            level-number
             +--ro corrupted-lsps?                  uint32
             +--ro authentication-type-fails?       uint32
             +--ro authentication-fails?            uint32
             +--ro database-overload?               uint32
             +--ro own-lsp-purge?                   uint32
             +--ro manual-address-drop-from-area?   uint32
             +--ro max-sequence?                    uint32
             +--ro sequence-number-skipped?         uint32
             +--ro id-len-mismatch?                 uint32
             +--ro partition-changes?               uint32
             +--ro lsp-errors?                      uint32
             +--ro spf-runs?                        uint32

  rpcs:
    +---x clear-adjacency
    |  +---w input
    |     +---w routing-protocol-instance-name    instance-state-ref
    |     +---w level?                            level
    |     +---w interface?                        string
    +---x clear-database
       +---w input
          +---w routing-protocol-instance-name    instance-state-ref
          +---w level?                            level

  notifications:
    +---n database-overload
    |  +--ro routing-instance?        string
    |  +--ro routing-protocol-name?   string
    |  +--ro isis-level?              level
    |  +--ro overload?                enumeration
    +---n lsp-too-large
    |  +--ro routing-instance?        string
    |  +--ro routing-protocol-name?   string
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro pdu-size?                uint32
    |  +--ro lsp-id?                  lsp-id
    +---n if-state-change
    |  +--ro routing-instance?        string
    |  +--ro routing-protocol-name?   string
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro state?                   if-state-type
    +---n corrupted-lsp-detected
    |  +--ro routing-instance?        string
    |  +--ro routing-protocol-name?   string
    |  +--ro isis-level?              level
    |  +--ro lsp-id?                  lsp-id
    +---n attempt-to-exceed-max-sequence
    |  +--ro routing-instance?        string
    |  +--ro routing-protocol-name?   string
    |  +--ro isis-level?              level
    |  +--ro lsp-id?                  lsp-id
    +---n id-len-mismatch
    |  +--ro routing-instance?        string
    |  +--ro routing-protocol-name?   string
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro pdu-field-len?           uint8
    |  +--ro raw-pdu?                 binary
    +---n max-area-addresses-mismatch
    |  +--ro routing-instance?        string
    |  +--ro routing-protocol-name?   string
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro max-area-addresses?      uint8
    |  +--ro raw-pdu?                 binary
    +---n own-lsp-purge
    |  +--ro routing-instance?        string
    |  +--ro routing-protocol-name?   string
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro lsp-id?                  lsp-id
    +---n sequence-number-skipped
    |  +--ro routing-instance?        string
    |  +--ro routing-protocol-name?   string
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro lsp-id?                  lsp-id
    +---n authentication-type-failure
    |  +--ro routing-instance?        string
    |  +--ro routing-protocol-name?   string
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro raw-pdu?                 binary
    +---n authentication-failure
    |  +--ro routing-instance?        string
    |  +--ro routing-protocol-name?   string
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro raw-pdu?                 binary
    +---n version-skew
    |  +--ro routing-instance?        string
    |  +--ro routing-protocol-name?   string
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro protocol-version?        uint8
    |  +--ro raw-pdu?                 binary
    +---n area-mismatch
    |  +--ro routing-instance?        string
    |  +--ro routing-protocol-name?   string
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro raw-pdu?                 binary
    +---n rejected-adjacency
    |  +--ro routing-instance?        string
    |  +--ro routing-protocol-name?   string
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro raw-pdu?                 binary
    |  +--ro reason?                  string
    +---n protocols-supported-mismatch
    |  +--ro routing-instance?        string
    |  +--ro routing-protocol-name?   string
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro raw-pdu?                 binary
    |  +--ro protocols*               uint8
    +---n lsp-error-detected
    |  +--ro routing-instance?        string
    |  +--ro routing-protocol-name?   string
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro lsp-id?                  lsp-id
    |  +--ro raw-pdu?                 binary
    |  +--ro error-offset?            uint32
    |  +--ro tlv-type?                uint8
    +---n adjacency-state-change
    |  +--ro routing-instance?        string
    |  +--ro routing-protocol-name?   string
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro neighbor?                string
    |  +--ro neighbor-system-id?      system-id
    |  +--ro state?                   adj-state-type
    |  +--ro reason?                  string
    +---n lsp-received
    |  +--ro routing-instance?        string
    |  +--ro routing-protocol-name?   string
    |  +--ro isis-level?              level
    |  +--ro interface-name?          string
    |  +--ro interface-level?         level
    |  +--ro extended-circuit-id?     extended-circuit-id
    |  +--ro lsp-id?                  lsp-id
    |  +--ro sequence?                uint32
    |  +--ro received-timestamp?      yang:timestamp
    |  +--ro neighbor-system-id?      system-id
    +---n lsp-generation
       +--ro routing-instance?        string
       +--ro routing-protocol-name?   string
       +--ro isis-level?              level
       +--ro lsp-id?                  lsp-id
       +--ro sequence?                uint32 sequence?                uint32
       +--ro send-timestamp?          yang:timestamp

2.5.  Authentication Parameters

   The module enables authentication enables authentication configuration through the IETF key-
   chain module ([RFC8177]).  The IS-IS module imports the "ietf-key-
   chain" module and reuses some groupings to allow global and per
   interface configuration of authentication.  If a global
   authentication is configured, an implementation SHOULD authenticate
   PSNPs, CSNPs and LSPs with the authentication parameters supplied.
   The authentication of hello PDUs can be activated on a per interface
   basis.

2.6.  IGP/LDP synchronization

   [RFC5443] defines a mechanism where IGP needs to be synchronized with
   LDP.  An "ldp-igp-sync" feature has been defined in the model to
   support this mechanism.  The "mpls/ldp/igp-sync" leaf under
   "interface" allows activation of the mechanism on a per interface
   basis.  The "mpls/ldp/igp-sync" container in the global configuration
   is empty on purpose and is not required for the activation.  The goal
   of this empty container is to allow easy augmentation with additional
   parameters like timers for example.

2.7.  ISO parameters

   As IS-IS protocol is based on ISO protocol suite, some ISO parameters
   may be required.

   This module augments interface configuration through model to support ISO
   configuration parameters.

   The clns-mtu can be defined under the IETF key-
   chain module ([I-D.ietf-rtgwg-yang-key-chain]). interface.

2.8.  IP FRR

   This YANG model supports LFA ([RFC5286]) and remote LFA ([RFC7490])
   as IP FRR techniques.  The IS-IS module
   imports "fast-reroute" container may be augmented
   by other models to support other IPFRR flavors (MRT, TILFA ...).

   The current version of the "ietf-key-chain" module model supports activation of LFA and reuses some groupings
   remote LFA at interface only.  The global "lfa" container is present
   but kept empty to allow augmentation with vendor specific properties
   like policies.

   Remote LFA is considered as a child of LFA.  Remote LFA cannot be
   enabled if LFA is not enabled.

   The "candidate-disabled" allows to mark an interface to not be used
   as a backup.

2.9.  Operational States

   Operational states are provided in the module in various places:

   o  system-counters: provides statistical informations about the
      global and per system.

   o  interface : provides configuration of authentication.  If state informations for each
      interface.

   o  adjacencies: provides state informations about current IS-IS
      adjacencies.

   o  spf-log: provides informations about SPF events on the node.  This
      SHOULD be implemented as a
   global authentication is configured, wrapping buffer.

   o  lsp-log: provides informations about LSP events on the node
      (reception of an implementation LSP or modification of local LSP).  This SHOULD
   authenticate PSNPs, CSNPs
      be implemented as a wrapping buffer and an implementation MAY
      decide to log refresh LSPs with or not.

   o  local-rib: provides the authentication parameters
   supplied. IS-IS internal routing table view.

   o  database: provides details on the current LSDB.

   o  hostnames: provides informations about system-id to hostname
      mappings.

   o  fast-reroute: provides informations about IP FRR.

3.  RPC Operations

   The authentication "ietf-isis" module defines two RPC operations:

   o  clear-database: reset the content of hello PDUs can be activated on a per
   interface basis.

2.6.  IGP/LDP particular IS-IS database
      and restart database synchronization

   [RFC5443] defines a mechanism where IGP needs to be synchronized with
   LDP.  An "ldp-igp-sync" feature has been defined in the model to
   support this mechanism.  The "mpls/ldp/igp-sync" leaf under
   "interface" allows activation neighbors.

   o  clear-adjacency: restart a particular set of IS-IS adjacencies.

4.  Notifications

   The "ietf-isis" module introduces some notifications :

      database-overload: raised when overload condition is changed.

      lsp-too-large: raised when the mechanism on system tries to propagate a per too
      large PDU.

      if-state-change: raise when the state of an interface
   basis.  The "mpls/ldp/igp-sync" container in changes.

      corrupted-lsp-detected: raised when the global configuration
   is empty on purpose and system find that an LSP
      that was stored in memory has become corrupted.

      attempt-to-exceed-max-sequence: This notification is not required for sent when the activation.  The goal
      system wraps the 32-bit sequence counter of this empty container an LSP.

      id-len-mismatch: This notification is to allow easy augmentation sent when we receive a PDU
      with additional
   parameters like timers a different value for example.

2.7.  ISO parameters

   As IS-IS protocol is based on ISO protocol suite, some ISO parameters
   may be required. the System ID length.

      max-area-addresses-mismatch: This module augments interface configuration model to support ISO
   configuration parameters.

   The clns-mtu can be defined under notification is sent when we
      receive a PDU with a different value for the interface.

2.8.  IP FRR Maximum Area
      Addresses.

      own-lsp-purge: This YANG model supports LFA ([RFC5286]) notification is sent when the system receives
      a PDU with its own system ID and remote LFA ([RFC7490])
   as IP FRR techniques.  The "fast-reroute" container may be augmented
   by other models to support other IPFRR flavors (MRT, TILFA ...).

   The current version of zero age.

      sequence-number-skipped: This notification is sent when the model supports activation of LFA system
      receives a PDU with its own system ID and
   remote LFA at interface only. different contents.  The global "lfa" container is present
   but kept empty
      system has to allow augmentation reissue the LSP with vendor specific properties
   like policies.

   Remote LFA a higher sequence number.

      authentication-type-failure: This notification is considered as sent when the
      system receives a child of LFA.  Remote LFA cannot be
   enabled if LFA PDU with the wrong authentication type field.

      authentication-failure: This notification is not enabled.

   The "candidate-disabled" allows to mark an interface to not be used
   as sent when the system
      receives a backup.

2.9.  Operational States

   Operational states are provided in PDU with the module in various places:

   o  system-counters: provides statistical informations about wrong authentication information.

      version-skew: This notification is sent when the
      global system.

   o  interface : provides configuration state informations for each
      interface.

   o  adjacencies: provides state informations about current IS-IS
      adjacencies.

   o  spf-log: provides informations about SPF events on system receives a
      PDU with a different protocol version number.

      area-mismatch: This notification is sent when the system receives
      a Hello PDU from an IS that does not share any area address.

      rejected-adjacency: This notification is sent when the node. system
      receives a Hello PDU from an IS but does not establish an
      adjacency for some reason.

      protocols-supported-mismatch: This
      SHOULD be implemented as notification is sent when the
      system receives a wrapping buffer.

   o  lsp-log: provides informations about non pseudonode LSP events on that has no matching protocol
      supported.

      lsp-error-detected: This notification is sent when the node
      (reception of an system
      receives a LSP or modification of local LSP).  This SHOULD
      be implemented as with a wrapping buffer and parse error.

      adjacency-state-change: This notification is sent when an implementation MAY
      decide IS-IS
      adjacency moves to log refresh LSPs Up state or not.

   o  local-rib: provides the IS-IS internal routing table view.

   o  database: provides details on the current LSDB.

   o  hostnames: provides informations about system-id to hostname
      mappings.

   o  fast-reroute: provides informations about IP FRR.

3.  RPC Operations

   The "ietf-isis" module defines two RPC operations:

   o  clear-isis-database: reset the content of Down state.

      lsp-received: This notification is sent when a particular IS-IS
      database and restart database synchronization LSP is received.

      lsp-generation: This notification is sent when a LSP is
      regenerated.

5.  Interaction with Other YANG Modules

   The "isis" configuration container augments the neighbors.

   o  clear-isis-adjacency: restart a particular set "/rt:routing/
   rt:control-plane-protocols/control-plane-protocol" container of the
   ietf-routing [RFC8349] module by defining IS-IS
      adjacencies.

4.  Notifications specific parameters.

   The "ietf-isis" "isis" module introduces some notifications :

      database-overload : raised when overload condition is changed.

      lsp-too-large : raised when augments "/if:interfaces/if:interface" defined by
   [RFC8343] with ISO specific parameters.

   The "isis" operational state container augments the system tries to propagate a too
      large PDU.

      corrupted-lsp-detected : raised when "/rt:routing-
   state/rt:control-plane-protocols/control-plane-protocol" container of
   the ietf-routing module by defining IS-IS specific operational
   states.

   Some IS-IS specific routes attributes are added to route objects of
   the system find that an LSP
      that was stored ietf-routing module by augmenting "/rt:routing-
   state/rt:ribs/rt:rib/rt:routes/rt:route".

   The modules defined in memory has become corrupted.

      attempt-to-exceed-max-sequence : This notification is sent when this document use some groupings from ietf-
   keychain [RFC8177].

   The module reuses types from [RFC6991] and [RFC8294].

   To support BFD for fast detection, the system wraps module relies on
   [I-D.ietf-bfd-yang].

6.  IS-IS YANG Module

<CODE BEGINS> file "ietf-isis@2018-11-26.yang"

module ietf-isis {
  yang-version 1.1;
  namespace "urn:ietf:params:xml:ns:yang:ietf-isis";

  prefix isis;

  import ietf-routing {
    prefix "rt";
    reference "RFC 8349 - A YANG Data Model for Routing
               Management (NMDA Version)";
  }

  import ietf-inet-types {
    prefix inet;
    reference "RFC 6991 - Common YANG Data Types";
  }

  import ietf-yang-types {
    prefix yang;
    reference "RFC 6991 - Common YANG Data Types";
  }

  import ietf-interfaces {
    prefix "if";
    reference "RFC 8343 - A YANG Data Model for Interface
               Management (NDMA Version)";
  }

  import ietf-key-chain {
    prefix "key-chain";
    reference "RFC 8177 - YANG Data Model for Key Chains";
  }

  import ietf-routing-types {
    prefix "rt-types";
    reference "RFC 8294 - Common YANG Data Types for the 32-bit sequence counter of an LSP.

      id-len-mismatch : This notification is sent when we receive a PDU
               Routing Area";
  }

  import iana-routing-types {
    prefix "iana-rt-types";
    reference "RFC 8294 - Common YANG Data Types for the
               Routing Area";
  }

  import ietf-bfd-types {
    prefix "bfd-types";
    reference "RFC XXXX - YANG Data Model for Bidirectional
               Forwarding Detection (BFD).Please replace YYYY with a different value
                                                         published RFC
number for draft-ietf-bfd-yang.";
  }

  organization
    "IETF LSR Working Group";

  contact
    "WG List:  &lt;mailto:lsr@ietf.org&gt;

    Editor:    Stephane Litkowski
          &lt;mailto:stephane.litkowski@orange.com&gt;

        Derek Yeung
          &lt;mailto:derek@arrcus.com&gt;
        Acee Lindem
          &lt;mailto:acee@cisco.com&gt;
        Jeffrey Zhang
          &lt;mailto:zzhang@juniper.net&gt;
        Ladislav Lhotka
          &lt;mailto:llhotka@nic.cz&gt;
        Yi Yang
          &lt;mailto:yiya@cisco.com&gt;
        Dean Bogdanovic
          &lt;mailto:deanb@juniper.net&gt;
        Kiran Agrahara Sreenivasa
          &lt;mailto:kkoushik@brocade.com&gt;
        Yingzhen Qu
          &lt;mailto:yiqu@cisco.com&gt;
        Jeff Tantsura
          &lt;mailto:jefftant.ietf@gmail.com&gt;

    ";

  description
    "This YANG module defines the System ID length.

      max-area-addresses-mismatch : This notification is sent when we
      receive a PDU with a different value generic configuration and
      operational state for the Maximum Area
      Addresses.

      own-lsp-purge : This notification IS-IS protocol.
                        It is sent when intended that the system receives
      a PDU with its own system ID module
      will be extended by vendors to define vendor-specific
      IS-IS configuration parameters and zero age.

      sequence-number-skipped : policies,
      for example route maps or route policies.

      This notification is sent when the
      system receives a PDU with its own system ID and different
      contents.  The system has YANG model conforms to reissue the LSP with a higher
      sequence number.

      authentication-type-failure : This notification is sent when the
      system receives a PDU with Network Management
      Datastore Architecture (NDMA) as described in RFC 8242.

      Copyright (c) 2018 IETF Trust and the wrong authentication type field.

      authentication-failure : This notification is sent when persons identified as
      authors of the system
      receives a PDU code.  All rights reserved.

       Redistribution and use in source and binary forms, with the wrong authentication information.

      version-skew : This notification or
       without modification, is sent when permitted pursuant to, and subject
       to the system receives
      a PDU with a different protocol version number.

      area-mismatch : This notification is sent when license terms contained in, the system receives
      a Hello PDU from an IS that does not share any area address.

      rejected-adjacency : This notification is sent when Simplified BSD License
       set forth in Section 4.c of the system
      receives a Hello PDU from an IS but does not establish an
      adjacency for some reason.

      protocols-supported-mismatch : IETF Trust's Legal Provisions
       Relating to IETF Documents
       (http://trustee.ietf.org/license-info).

       This notification version of this YANG module is sent when part of RFC XXXX;
       see the
      system receives a non pseudonode RFC itself for full legal notices.";

  revision 2018-11-26 {
    description
      "Initial revision.";
    reference "RFC XXXX";
  }

  /* Identities */

  identity isis {
    base rt:routing-protocol;
    description "Identity for the IS-IS routing protocol.";
  }

  identity lsp-log-reason {
    description "Base identity for an LSP that has no matching protocol
      supported.

      lsp-error-detected : This notification is sent change log reason.";
  }

  identity refresh {
    base lsp-log-reason;
    description
      "Identity used when the system
      receives a LSP with a parse error.

      adjacency-change : This notification is sent when an IS-IS
      adjacency moves to Up state or to Down state.

      lsp-received : This notification log reason is sent when
       a refresh LSP is received.

      lsp-generation : This notification is sent received.";
  }

  identity content-change {
    base lsp-log-reason;
    description
      "Identity used when a the LSP log reason is
      regenerated.

5.  Interaction with Other YANG Modules

   The "isis" configuration container augments
       a change in the "/rt:routing/
   rt:control-plane-protocols/control-plane-protocol" container content of the
   ietf-routing [I-D.ietf-netmod-routing-cfg] module by defining IS-IS
   specific parameters.

   The "isis" module augments "/if:interfaces/if:interface" with ISO
   specific parameters.

   The "isis" operational LSP.";
  }
  /* Feature definitions */

  feature poi-tlv {
    description "Support of Purge Originator Identification.";
    reference "RFC 6232 - Purge Originator Identification TLV
               for IS-IS";
  }
  feature ietf-spf-delay {
    description
      "Support for IETF SPF delay algorithm.";
    reference "RFC 8405 - SPF Back-off algorithm for link
               state container augments the "/rt:routing-
   state/rt:control-plane-protocols/control-plane-protocol" container IGPs";
  }
  feature bfd {
    description
      "Support for BFD detection of
   the ietf-routing module by defining IS-IS specific operational
   states.

   Some neighbor reachability.";
    reference "RFC 5880 - Bidirectional Forwarding Detection (BFD)
               RFC 5881 - Bidirectional Forwarding Detection
               (BFD) for IPv4 and IPv6 (Single Hop)";
  }
  feature key-chain {
    description
      "Support of keychain for authentication.";
    reference "RFC8177 - YANG Data Model for Key Chains";
  }
  feature node-flag {
    description
      "Support for node-flag for IS-IS prefixes.";
    reference "RFC7794 - IS-IS specific routes attributes are added to route objects Prefix Attributes for
               Extended IP and IPv6 Reachability";
  }
  feature node-tag {
    description
      "Support for node admin tag for IS-IS routing instances.";
    reference "RFC7917 - Advertising Node Administrative Tags
               in IS-IS";
  }
  feature ldp-igp-sync {
    description
      "LDP IGP synchronization.";
    reference "RFC5443 - LDP IGP Synchronization.";
  }
  feature fast-reroute {
    description
      "Support for IP Fast Reroute (IP-FRR).";
  }
  feature nsr {
    description
      "Non-Stop-Routing (NSR) support.";
  }
  feature lfa {
    description
      "Support for Loop-Free Alternates (LFAs).";
    reference "RFC5286 - Basic Specification of
   the ietf-routing module IP Fast-Reroute:
               Loop-free Alternates";
  }
  feature remote-lfa {
    description
      "Support for Remote Loop-Free Alternates (R-LFAs).";
    reference "RFC7490 - Remote Loop-Free Alternate Fast Reroute";
  }

  feature overload-max-metric {
    description
      "Support of overload by augmenting "/rt:routing-
   state/rt:ribs/rt:rib/rt:routes/rt:route".

   The modules defined setting
       all links to max metric.";
  }
  feature prefix-tag {
    description
      "Support for 32-bit prefix tags";
    reference "RFC5130 - A Policy Control Mechanism in this document use some groupings from ietf-
   keychain [I-D.ietf-rtgwg-yang-key-chain].

6.
               IS-IS YANG Module

   <CODE BEGINS> file "ietf-isis@2018-08-09.yang"

   module ietf-isis Using Administrative Tags";
  }
  feature prefix-tag64 {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:ietf-isis";
    description
      "Support for 64-bit prefix isis;

     import ietf-routing tags";
    reference "RFC5130 - A Policy Control Mechanism in
               IS-IS Using Administrative Tags";
  }
  feature auto-cost {
    description
      "Calculate IS-IS interface metric according to
       reference bandwidth.";
  }

  feature te-rid {
    description
      "Traffic-Engineering Router-ID.";
    reference "RFC5305 - IS-IS Extensions for Traffic Engineering
               RFC6119 - IPv6 Traffic Engineering in IS-IS";
  }
  feature max-ecmp {
    description
      "Setting maximum number of ECMP paths.";
  }
  feature multi-topology {
       prefix "rt";
    description
      "Support for Multiple-Topology Routing (MTR).";
    reference "RFC 8349 "RFC5120 - A YANG Data Model for M-IS-IS: Multi Topology Routing
                  Management (NMDA Version)"; in IS-IS";
  }

     import ietf-inet-types
  feature nlpid-control {
       prefix inet;
       reference "RFC 6021 - Common YANG Data Types";
    description
      "This feature controls the advertisement
       of support NLPID within IS-IS configuration.";
  }

     import ietf-yang-types
  feature graceful-restart {
       prefix yang;
    description
      "IS-IS Graceful restart support.";
    reference "RFC 6021 "RFC5306 - Common YANG Data Types"; Restart Signaling in IS-IS";
  }

     import ietf-interfaces

  feature lsp-refresh {
       prefix "if";
       reference "RFC 8343 - A YANG Data Model for Interface
                  Management (NDMA Version)";
    description
      "Configuration of LSP refresh interval.";
  }

     import ietf-key-chain

  feature maximum-area-addresses {
       prefix "key-chain";
       reference "RFC 8177 - YANG Data Model for Key Chains";
    description
      "Support of maximum-area-addresses config.";
  }

     import ietf-routing-types

  feature admin-control {
       prefix "rt-types";
       reference "RFC 8291 - Common YANG Data Types for
    description
      "Administrative control of the
                  Routing Area"; protocol state.";
  }

     import iana-routing-types

  /* Type definitions */

  typedef circuit-id {
       prefix "iana-rt-types";
       reference "RFC 8291 - Common YANG Data Types for
    type uint8;
    description
      "This type defines the
                  Routing Area"; circuit ID
       associated with an interface.";
  }

     import ietf-bfd-types

  typedef extended-circuit-id {
       prefix "bfd-types";
       reference "RFC XXXX - YANG Data Model for Bidirectional
                  Forwarding Detection (BFD)";
    type uint32;
    description
      "This type defines the extended circuit ID
       associated with an interface.";
  }

     organization
       "IETF IS-IS Working Group";

     contact
       "WG List:  &lt;mailto:isis-wg@ietf.org&gt;

       Editor:    Stephane Litkowski
             &lt;mailto:stephane.litkowski@orange.com&gt;

           Derek Yeung
             &lt;mailto:derek@arrcus.com&gt;
           Acee Lindem
             &lt;mailto:acee@cisco.com&gt;
           Jeffrey Zhang
             &lt;mailto:zzhang@juniper.net&gt;
           Ladislav Lhotka
             &lt;mailto:llhotka@nic.cz&gt;
           Yi Yang
             &lt;mailto:yiya@cisco.com&gt;
           Dean Bogdanovic
             &lt;mailto:deanb@juniper.net&gt;
           Kiran Agrahara Sreenivasa
             &lt;mailto:kkoushik@brocade.com&gt;
           Yingzhen Qu
             &lt;mailto:yiqu@cisco.com&gt;
                   Jeff Tantsura
                     &lt;mailto:jefftant.ietf@gmail.com&gt;

       ";

  typedef interface-type {
    type enumeration {
      enum broadcast {
        description
          "Broadcast interface type.";
      }
      enum point-to-point {
        description
       "The YANG module
          "Point-to-point interface type.";
      }
    }
    description
      "This type defines a generic configuration model for
        IS-IS common across all the type of adjacency
       to be established on the vendor implementations.";

     revision 2018-08-09 interface.
       The interface-type determines the type
       of hello message that is used.";

  }

  typedef level {
    type enumeration {
      enum "level-1" {
        description
         "Initial revision.";
       reference "RFC XXXX";
          "This enum indicates L1-only capability.";
      }

     /* Identities */

     identity isis
      enum "level-2" {
       base rt:routing-protocol;
        description "Identity for the IS-IS routing protocol.";
          "This enum indicates L2-only capability.";
      }

     identity isis-adjacency-change
      enum "level-all" {
        description "Identity
          "This enum indicates capability for the IS-IS routing protocol
                    adjacency state."; both levels.";
      }

     identity clear-isis-database {
    }
    default "level-all";
    description "Identity for the
      "This type defines IS-IS routing protocol
                    database reset action."; level of an object.";

  }

     identity clear-isis-adjacency

  typedef adj-state-type {
    type enumeration {
      enum "up" {
        description "Identity for
          "State indicates the IS-IS routing protocol adjacency reset action."; is established.";
      }

     identity lsp-log-reason
      enum "down" {
        description "Base identity for an LSP change log reason.";
          "State indicates the adjacency is NOT established.";
      }

     identity refresh
      enum "init" {
       base lsp-log-reason;
        description
         "Identity used when
          "State indicates the LSP log reason adjacency is
          a refresh LSP received."; establishing.";
      }

     identity content-change
      enum "failed" {
       base lsp-log-reason;
        description
         "Identity used when
          "State indicates the LSP log reason adjacency is
          a change in the content of the LSP."; failed.";
      }

     /* Feature definitions */

     feature ietf-spf-delay {
       description
         "Support of IETF SPF delay algorithm.";
       reference "RFC XXXX - SPF Back-off algorithm for link
                  state IGPs";
    }
     feature bfd {
    description
         "Support for BFD detection of IS-IS neighbor reachability.";
       reference "RFC 5880 - Bidirectional Forwarding Detection (BFD)
                  RFC 5881 - Bidirectional Forwarding Detection
                  (BFD) for IPv4 and IPv6 (Single Hop)";
      "This type defines states of an adjacency";
  }
     feature key-chain

  typedef if-state-type {
    type enumeration {
      enum "up" {
        description
         "Support of keychain for authentication.";
       reference "RFC8177 - YANG Data Model for Key Chains"; "Up state.";

      }
     feature node-flag
      enum "down" {
        description
         "Support "Down state";
      }
    }
    description
      "This type defines the state of node-flag advertisement
          as prefix attribute";
       reference "RFC7794 - IS-IS Prefix Attributes for
                  Extended IP and IPv6 Reachability"; an interface";
  }
     feature node-tag

  typedef level-number {
    type uint8 {
      range "1 .. 2";
    }
    description
         "Support of node tag.";
       reference "RFC7917 - Advertising Node Administrative Tags
                  in IS-IS";
      "This type defines the current IS-IS level.";
  }
     feature ldp-igp-sync

  typedef lsp-id {
    type string {
      pattern
        '[0-9A-Fa-f]{4}\.[0-9A-Fa-f]{4}\.[0-9A-Fa-f]'
        +'{4}\.[0-9][0-9]-[0-9][0-9]';
    }
    description
         "Support of synchronization between
      "This type defines the IS-IS and LDP.";
       reference "RFC5443 - LDP IGP Synchronization"; LSP ID format using a
       pattern, An example LSP ID is 0143.0438.AEF0.02-01";
  }
     feature fast-reroute

  typedef area-address {
    type string {
      pattern '[0-9A-Fa-f]{2}(\.[0-9A-Fa-f]{4}){0,3}';
    }
    description
         "Support of IP Fast Reroute.";
      "This type defines the area address format.";
  }
     feature nsr

  typedef snpa {
    type string {
      length "0 .. 20";
    }
    description
         "Support
      "This type defines the Subnetwork Point
       of Non-Stop Routing."; Attachement (SNPA) format.";
  }
     feature lfa

  typedef system-id {
    type string {
      pattern
        '[0-9A-Fa-f]{4}\.[0-9A-Fa-f]{4}\.[0-9A-Fa-f]{4}';
    }
    description
         "Support of Loop-Free Alternates.";
       reference "RFC5286 - Basic Specification of IP Fast-Reroute:
                  Loop-free Alternates";
      "This type defines IS-IS system-id using pattern,
       An example system-id is 0143.0438.AEF0";
  }
     feature remote-lfa
        typedef extended-system-id {
    type string {
      pattern
        '[0-9A-Fa-f]{4}\.[0-9A-Fa-f]{4}\.[0-9A-Fa-f]{4}\.[0-9][0-9]';
    }
    description
         "Support of remote Loop Free Alternates.";
       reference "RFC7490 - Remote Loop-Free Alternate Fast Reroute";
      "This type defines IS-IS system-id using pattern. The extended
                         system id contains the pseudonode number in
addition to the
                         system id.
       An example system-id is 0143.0438.AEF0.00";
  }

     feature overload-max-metric

  typedef wide-metric {
    type uint32 {
      range "0 .. 16777215";
    }
    description
         "Support
      "This type defines wide style format of overload by setting
          all links to max IS-IS metric.";
  }
     feature prefix-tag

  typedef std-metric {
    type uint8 {
      range "0 .. 63";
    }
    description
         "Support for 32-bit prefix tags";
       reference "RFC5130 - A Policy Control Mechanism in
      "This type defines old style format of IS-IS Using Administrative Tags"; metric.";
  }
     feature prefix-tag64

  typedef mesh-group-state {
    type enumeration {
      enum "mesh-inactive" {
        description
         "Support for 64-bit prefix tags";
       reference "RFC5130 - A Policy Control Mechanism in
                  IS-IS Using Administrative Tags";
          "Interface is not part of a mesh group.";
      }
     feature auto-cost
      enum "mesh-set" {
        description
         "Use an automated assignment
          "Interface is part of metrics."; a mesh group.";
      }

     feature te-rid
      enum "mesh-blocked" {
        description
         "Traffic-Engineering Router-ID.";
       reference "RFC5305 - IS-IS Extensions for Traffic Engineering
                  RFC6119 - IPv6 Traffic Engineering in IS-IS";
          "LSPs must not be flooded over this interface.";
      }
    }
     feature max-ecmp {
    description
         "Setting maximum number
      "This type describes mesh group state of ECMP paths."; an interface";
  }
     feature multi-topology

  /* Grouping for notifications */

  grouping notification-instance-hdr {
    description
         "Multitopology routing support.";
       reference "RFC5120 - M-IS-IS: Multi Topology Routing in IS-IS";
     }
     feature nlpid-control
      "Instance specific IS-IS notification data grouping";
    leaf routing-protocol-name {
      type leafref {
        path "/rt:routing/rt:control-plane-protocols/"
           + "rt:control-plane-protocol/rt:name";
      }
      description
         "This feature controls the advertisement "Name of support NLPID within the IS-IS configuration."; instance.";
    }
     feature graceful-restart
    leaf isis-level {
      type level;
      description
         "Graceful restart support.";
       reference "RFC5306 - Restart Signaling in IS-IS"; "IS-IS level of the instance.";
    }

     feature lsp-refresh
  }

  grouping notification-interface-hdr {
    description
         "Configuration of LSP refresh interval.";
      "Interface specific IS-IS notification data grouping";
    leaf interface-name {
      type if:interface-ref;
      description "IS-IS interface name";
    }

     feature maximum-area-addresses
    leaf interface-level {
      type level;
      description
         "Support of maximum-area-addresses config."; "IS-IS level of the interface.";
    }

     feature admin-control
    leaf extended-circuit-id {
      type extended-circuit-id;
      description
         "Control administrative state "Eextended circuit-id of IS-IS."; the interface.";
    }
  }

 /* Type definitions Groupings for IP Fast Reroute */

     typedef instance-state-ref

 grouping instance-fast-reroute-config {
       type leafref
    description
      "This group defines global configuration of IP
       Fast ReRoute (FRR).";
    container fast-reroute {
         path "/rt:routing-state/"
           +"rt:control-plane-protocols/rt:control-plane-protocol/"
           +"rt:name";
       }
      if-feature fast-reroute;
      description
        "This type is used for leaves that reference state data container may be augmented with global
         parameters for
          an IS-IS protocol instance.";
     }

     typedef circuit-id IP-FRR.";
      container lfa {
       type uint8;
        if-feature lfa;
        description
          "This type defines the circuit ID
          associated container may be augmented with an interface.";
           global parameters for Loop-Free Alternatives (LFA).
           Container creation has no effect on LFA activation.";
      }

     typedef extended-circuit-id
    }
  }

 grouping interface-lfa-config {
    leaf candidate-enable {
      type uint32; boolean;
      default true;
      description
         "This type defines
        "Enable the extended circuit ID
          associated with an interface."; interface to be used as backup.";
    }

     typedef interface-type
    leaf enable {
      type enumeration boolean;
      default false;
      description
        "Activates LFA - Per-prefix LFA computation
         is assumed.";
    }
    container remote-lfa {
         enum broadcast
      if-feature remote-lfa;
      leaf enable {
        type boolean;
        default false;
        description
             "Broadcast interface type.";
          "Activates Remote LFA (R-LFA).";
      }
         enum point-to-point {
      description
             "Point-to-point interface type.";
        "Remote LFA configuration.";
    }
    description "Grouping for LFA interface configuration";
  }
  grouping interface-fast-reroute-config {
    description
      "This type group defines the type of adjacency
          to be established on the interface.
          The interface-type determines the type interface configuration of hello message that is used."; IP-FRR.";
    container fast-reroute {
      if-feature fast-reroute;
      container lfa {
        if-feature lfa;
        uses interface-lfa-config;
        container level-1 {
          uses interface-lfa-config;
          description
            "LFA level 1 config";
        }

     typedef
        container level-2 {
        uses interface-lfa-config;
         description
          "LFA level 2 config";
        }
        description
          "LFA configuration.";
      }
      description
        "Interface IP Fast-reroute configuration.";
    }
  }
  grouping instance-fast-reroute-state {
    description "IPFRR state data grouping";

    container protected-routes {
      config false;
      list address-family-stats {
        key "address-family prefix alternate";

        leaf address-family {
          type enumeration {
         enum "level-1" { iana-rt-types:address-family;
          description
             "This enum indicates L1-only capability.";
            "Address-family";

        }
         enum "level-2"
        leaf prefix {
          type string;
          description
             "This enum indicates L2-only capability.";
            "Protected prefix.";
        }
         enum "level-all"
        leaf alternate {
          type string;
          description
             "This enum indicates capability
            "Alternate nexthop for both levels.";
         }
       }
       default "level-all";
       description
         "This type defines IS-IS level of an object."; the prefix.";
        }

     typedef adj-state-type
        leaf alternate-type {
          type enumeration {
            enum "up" equal-cost {
              description
             "State indicates the adjacency is established.";
                "ECMP alternate.";
            }
            enum "down" lfa {
              description
             "State indicates the adjacency is NOT established.";
                "LFA alternate.";
            }
            enum "init" remote-lfa {
              description
             "State indicates the adjacency is establishing.";
                "Remote LFA alternate.";
            }
            enum "failed" tunnel {
              description
             "State indicates the adjacency is failed.";
         }
                "Tunnel based alternate
                 (like RSVP-TE or GRE).";
            }
            enum ti-lfa {
              description
         "This type defines states of an adjacency";
                "TI-LFA alternate.";
            }

     typedef if-state-type {
       type enumeration {
            enum "up" mrt {
              description "Up state.";
                "MRT alternate.";
            }
            enum "down" other {
              description "Down state";
                "Unknown alternate type.";
            }
          }
          description
         "This type defines the state
            "Type of an interface";
     }

     typedef level-number {
       type uint8 {
         range "1 .. 2";
       }
       description
         "This type defines the current IS-IS level."; alternate.";
        }
     typedef lsp-id
        leaf best {
          type string {
         pattern
           '[0-9A-Fa-f]{4}\.[0-9A-Fa-f]{4}\.[0-9A-Fa-f]'
           +'{4}\.[0-9][0-9]-[0-9][0-9]';
       } boolean;
          description
         "This type defines
            "Indicates if the IS-IS LSP ID format using a
          pattern, An example LSP ID alternate is 0143.0438.AeF0.02-01";
     }

     typedef area-address {
       type string {
         pattern '[0-9A-Fa-f]{2}\.([0-9A-Fa-f]{4}\.){0,3}';
       }
       description
         "This type defines the area address format.";
     }

     typedef snpa {
       type string {
         length "0 .. 20";
       }
       description
         "This type defines the Subnetwork Point
          of Attachement (SNPA) format."; preferred.";
        }

     typedef system-id
        leaf non-best-reason {
          type string {
         pattern
           '[0-9A-Fa-f]{4}\.[0-9A-Fa-f]{4}\.[0-9A-Fa-f]{4}';
       } string;
          description
         "This type defines IS-IS system-id using pattern,
          An example system-id
            "Information field to describe why the alternate
             is 0143.0438.AeF0"; not best.";
        }

     typedef wide-metric
        leaf protection-available {
          type uint32 bits {
         range "0 .. 16777215";
            bit node-protect {
              position 0;
              description
                "Node protection available.";
            }
            bit link-protect {
              position 1;
              description
         "This type defines wide style format of IS-IS metric.";
                "Link protection available.";
            }

     typedef std-metric
            bit srlg-protect {
       type uint8
              position 2;
              description
                "SRLG protection available.";
            }
            bit downstream-protect {
         range "0 .. 63";
              position 3;
              description
                "Downstream protection available.";
            }
            bit other {
              position 4;
              description
         "This type defines old style format of IS-IS metric.";
                "Other protection available.";
            }

     typedef mesh-group-state
          }
          description "Protection provided by the alternate.";
        }
        leaf alternate-metric1 {
          type enumeration {
         enum "mesh-inactive" { uint32;
          description
             "Interface is not part
            "Metric from Point of a mesh group."; Local Repair (PLR) to
             destination through the alternate path.";
        }
         enum "mesh-set"
        leaf alternate-metric2 {
          type uint32;
          description
             "Interface is part of a mesh group.";
            "Metric from PLR to the alternate node";
        }
         enum "mesh-blocked"
        leaf alternate-metric3 {
          type uint32;
          description
             "LSPs must not be flooded over this interface.";
            "Metric from alternate node to the destination";
        }
        description
          "Per-AF protected prefix statistics.";
      }
      description
         "This type describes mesh group state
        "List of an interface"; prefixes that are protected.";
    }

     /* Grouping definitions for configuration and ops state */

     grouping adjacency-state {

    container adjacencies unprotected-routes {
      config false;
      list adjacency address-family-stats {
        key "address-family prefix";

        leaf neighbor-sys-type address-family {
          type level; iana-rt-types:address-family;

          description
               "Level capability of neighboring system"; "Address-family";
        }
        leaf neighbor-sysid prefix {
          type system-id; string;
          description
               "The system-id "Unprotected prefix.";
        }
        description
          "Per AF unprotected prefix statistics.";
      }
      description
        "List of the neighbor"; prefixes that are not protected.";
    }

    list protection-statistics {
      key frr-protection-method;
      config false;
      leaf neighbor-extended-circuit-id frr-protection-method {
        type extended-circuit-id; string;
        description
               "Circuit ID of the neighbor"; "Protection method used.";
      }
      list address-family-stats {
        key address-family;

        leaf neighbor-snpa address-family {
          type snpa; iana-rt-types:address-family;
          description
               "SNPA of the neighbor"; "Address-family";
        }
        leaf usage total-routes {
          type level; uint32;
          description
               "Define the level(s) activated on the adjacency.
                On a p2p link this might be level 1 and 2,
                but on a LAN, the usage will be level 1
                between peers at level 1 or level 2 between
                peers at level 2."; "Total prefixes.";
        }
        leaf hold-timer unprotected-routes {
          type rt-types:timer-value-seconds16;
             units seconds; uint32;
          description
               "The holding time in seconds for this
                adjacency. This value is based on
                received hello PDUs and the elapsed
                time since receipt.";
            "Total prefixes that are not protected.";
        }
        leaf neighbor-priority protected-routes {
          type uint8 {
               range "0 .. 127";
             } uint32;
          description
               "Priority of the neighboring IS for becoming
                the DIS.";
            "Total prefixes that are protected.";
        }
        leaf lastuptime linkprotected-routes {
          type yang:timestamp; uint32;
          description
               "When the adjacency most recently entered
                state 'up', measured in hundredths of a
                second since the last reinitialization of
                the network management subsystem.
                The value is 0 if the adjacency has never
                been in state 'up'.";
            "Total prefixes that are link protected.";
        }
        leaf state nodeprotected-routes {
          type adj-state-type; uint32;
          description
               "This leaf describes the state of the interface.";
            "Total prefixes that are node protected.";
        }
        description
             "List of operational adjacencies.";
          "Per AF protected prefix statistics.";
      }

      description
           "This container lists the adjacencies of
            the local node."; "Global protection statistics.";
    }
       description
         "Adjacency state";
  }

        /* Route table and local RIB groupings */

  grouping fast-reroute-global-state local-rib {
    description "Local-rib - RIB for Routes computed by the local
                 IS-IS routing instance.";
    container protected-routes local-rib {
      config false;
      description "Local-rib.";
      list af-stats route {
        key "af prefix alternate";

           leaf af {
             type iana-rt-types:address-family; "prefix";
        description
               "Address-family";
           } "Routes";
        leaf prefix {
          type string; inet:ip-prefix;
          description
               "Protected "Destination prefix.";

        }
        container next-hops {
          description "Next hops for the route.";
          list next-hop {
            key "next-hop";
            description "List of next hops for the route";
            leaf alternate outgoing-interface {
              type string; if:interface-ref;
              description
               "Alternate nexthop for
                "Name of the prefix."; outgoing interface.";
            }
            leaf alternate-type next-hop {
             type enumeration {
               enum equal-cost { inet:ip-address;
             description
                   "ECMP alternate."; "Nexthop address.";
            }
               enum lfa {
                 description
                   "LFA alternate.";
          }
               enum remote-lfa {
                 description
                   "Remote LFA alternate.";
        }
               enum tunnel
        leaf metric {
          type uint32;
          description
                   "Tunnel based alternate
                    (like RSVP-TE or GRE)."; "Metric for this route.";
        }
               enum ti-lfa
        leaf level {
          type level-number;
          description
                   "TI-LFA alternate."; "Level number for this route.";
        }
               enum mrt
        leaf route-tag {
          type uint32;
          description
                   "MRT alternate."; "Route tag for this route.";
        }
               enum other {
                 description
                   "Unknown alternate type.";
      }
    }
             description
               "Type of alternate.";
  }

  grouping route-content {
    description
      "IS-IS protocol-specific route properties grouping.";
    leaf best metric {
      type boolean; uint32;
      description
               "Indicates if the alternate is the preferred."; "IS-IS metric of a route.";
    }
           leaf non-best-reason
    leaf-list tag {
      type string; uint64;
      description
               "Information field to describe why
        "List of tags associated with the alternate
                is not best."; route. The leaf
         describes both 32-bit and 64-bit tags.";
    }
    leaf protection-available route-type {
      type bits enumeration {
               bit node-protect
        enum l2-up-internal {
                 position 0;
          description
                   "Node protection available."; "Level 2 internal route
                       and not leaked to a lower level";
        }
               bit link-protect
        enum l1-up-internal {
                 position 1;
          description
                   "Link protection available."; "Level 1 internal route
                       and not leaked to a lower level";
        }
               bit srlg-protect
        enum l2-up-external {
                 position 2;
          description
                   "SRLG protection available."; "Level 2 external route
                       and not leaked to a lower level";
        }
               bit downstream-protect
        enum l1-up-external {
                 position 3;
          description
                   "Downstream protection available."; "Level 1 external route
                       and not leaked to a lower level";
        }
               bit other
        enum l2-down-internal {
                 position 4;
                 description
                   "Other protection available.";
               }
             }
          description "Protection provided by the alternate."; "Level 2 internal route
                       and leaked to a lower level";
        }
           leaf alternate-metric1
        enum l1-down-internal {
             type uint32;
          description
               "Metric from Point of Local Repair (PLR) "Level 1 internal route
                       and leaked to
                destination through the alternate path."; a lower level";
        }
           leaf alternate-metric2
        enum l2-down-external {
             type uint32;
          description
               "Metric from PLR "Level 2 external route
                       and leaked to the alternate node"; a lower level";
        }
           leaf alternate-metric3
        enum l1-down-external {
             type uint32;
          description
               "Metric from alternate node "Level 1 external route
                       and leaked to the destination"; a lower level";
        }
           description
             "Per-AF protected prefix statistics.";
      }
      description
           "List of prefixes that are protected."; "IS-IS route type.";
    }
  }

        /* Grouping definitions for configuration and ops state */

  grouping adjacency-state {
    container unprotected-routes adjacencies {
      config false;
      list af-stats {
           key "af prefix";

           leaf af adjacency {
             type iana-rt-types:address-family;

             description "Address-family";
           }
        leaf prefix neighbor-sys-type {
          type string;
             description "Unprotected prefix.";
           }
           description
             "Per AF unprotected prefix statistics.";
         } level;
          description
           "List
            "Level capability of prefixes that are not protected."; neighboring system";
        }

       list protection-statistics {
         key frr-protection-method;
         config false;
        leaf frr-protection-method neighbor-sysid {
          type string; system-id;
          description "Protection method used.";
            "The system-id of the neighbor";
        }
         list af-stats {
           key af;
        leaf af neighbor-extended-circuit-id {
          type iana-rt-types:address-family; extended-circuit-id;
          description "Address-family";
            "Circuit ID of the neighbor";
        }
        leaf total-routes neighbor-snpa {
          type uint32; snpa;
          description "Total prefixes.";
            "SNPA of the neighbor";
        }
        leaf unprotected-routes usage {
          type uint32; level;
          description
               "Total prefixes that are not protected.";
            "Define the level(s) activated on the adjacency.
             On a p2p link this might be level 1 and 2,
             but on a LAN, the usage will be level 1
             between peers at level 1 or level 2 between
             peers at level 2.";
        }
        leaf protected-routes hold-timer {
          type uint32; rt-types:timer-value-seconds16;
          units seconds;
          description
               "Total prefixes that are protected.";
            "The holding time in seconds for this
             adjacency. This value is based on
             received hello PDUs and the elapsed
             time since receipt.";
        }
        leaf linkprotected-routes neighbor-priority {
          type uint32;
             description
               "Total prefixes that are link protected.";
           }
           leaf nodeprotected-routes uint8 {
             type uint32;
             description
               "Total prefixes that are node protected.";
           }
           description
             "Per AF protected prefix statistics.";

         }

         description "Global protection statistics.";
            range "0 .. 127";
          }
          description "IPFRR states.";
            "Priority of the neighboring IS for becoming
             the DIS.";
        }

     grouping notification-instance-hdr {
       description
         "Instance specific IS-IS notification data grouping";
        leaf routing-instance lastuptime {
          type string; yang:timestamp;
          description "Name
            "When the adjacency most recently entered
             state 'up', measured in hundredths of a
             second since the routing-instance instance."; last reinitialization of
             the network management subsystem.
             The value is 0 if the adjacency has never
             been in state 'up'.";
        }
        leaf routing-protocol-name state {
          type string; adj-state-type;
          description "Name
            "This leaf describes the state of the IS-IS instance."; interface.";
        }
       leaf isis-level {
         type level;

        description "IS-IS level
          "List of operational adjacencies.";
      }
      description
        "This container lists the adjacencies of
         the instance."; local node.";
    }
    description
      "Adjacency state";
  }

  grouping notification-interface-hdr admin-control {
       description
         "Interface specific IS-IS notification data grouping";
    leaf interface-name enable {
      if-feature admin-control;
      type string; boolean;
      default true;
      description "IS-IS interface name";
        "Enable/Disable the protocol.";
    }
       leaf interface-level {
         type level;
    description "IS-IS level of the interface.";
      "Grouping for admin control.";
  }

  grouping ietf-spf-delay {
    leaf extended-circuit-id initial-delay {
      type extended-circuit-id; rt-types:timer-value-milliseconds;
      units msec;
      description "Eextended circuit-id of the interface.";
       }
        "Delay used while in QUIET state (milliseconds).";
    }

     grouping route-content {
       description
         "IS-IS protocol-specific route properties grouping.";
    leaf metric short-delay {
      type uint32; rt-types:timer-value-milliseconds;
      units msec;
      description "IS-IS metric of a route.";
        "Delay used while in SHORT_WAIT state (milliseconds).";
    }
       leaf-list tag
    leaf long-delay {
      type uint64; rt-types:timer-value-milliseconds;
      units msec;
      description
           "List of tags associated with the route. The leaf
            describes both 32-bit and 64-bit tags.";
        "Delay used while in LONG_WAIT state (milliseconds).";
    }

    leaf route-type hold-down {
      type enumeration {
           enum l2-up-internal { rt-types:timer-value-milliseconds;
      units msec;
      description "Level 2 internal route
                          and not leaked
        "Timer used to a lower level"; consider an IGP stability period
                                 (milliseconds).";
    }
           enum l1-up-internal
    leaf time-to-learn {
      type rt-types:timer-value-milliseconds;
      units msec;
      description "Level 1 internal route
                          and not leaked
        "Duration used to a lower level";
           }
           enum l2-up-external {
             description "Level 2 external route
                          and not leaked learn all the IGP events
         related to a lower level"; single component failure (milliseconds).";
    }
           enum l1-up-external
    leaf current-state {
             description "Level 1 external route
                          and not leaked to a lower level";
           }
           enum l2-down-internal
      type enumeration {
             description "Level 2 internal route
                          and leaked to a lower level";
           }
        enum l1-down-internal "quiet" {
          description "Level 1 internal route
                          and leaked to a lower level"; "QUIET state";
        }
        enum l2-down-external "short-wait" {
          description "Level 2 external route
                          and leaked to a lower level"; "SHORT_WAIT state";
        }
        enum l1-down-external "long-wait" {
          description "Level 1 external route
                          and leaked to a lower level"; "LONG_WAIT state";
        }
      }
      config false;
      description "IS-IS route type.";
       }
        "Current SPF backoff algorithm state.";
    }

     grouping admin-control {
    leaf enable remaining-time-to-learn {
         if-feature admin-control;
      type boolean;
         default true; rt-types:timer-value-milliseconds;
      units "msec";
      config false;
      description
           "Control the administrative state.";
        "Remaining time until time-to-learn timer fires.";
    }
    leaf remaining-hold-down {
      type rt-types:timer-value-milliseconds;
      units "msec";
      config false;
      description
         "Grouping for admin control.";
        "Remaining time until hold-down timer fires.";
    }

     grouping fast-reroute-global-cfg
    leaf last-event-received {
      type yang:timestamp;
      config false;
      description
         "IPFRR global configuration grouping";
       container lfa
        "Time of last IGP event received";
    }
    leaf next-spf-time {
         if-feature lfa;
      type yang:timestamp;
      config false;
      description
           "This container may be augmented with global
            parameters for LFA. Creating the container
        "Time when next SPF has no
            effect on LFA activation."; been scheduled.";
    }
    leaf last-spf-time {
      type yang:timestamp;
      config false;
      description
        "Time of last SPF computation.";
    }
    description
      "Grouping for IETF SPF delay configuration and state.";
  }

  grouping fast-reroute-if-cfg node-tag-config {
    description
         "IPFRR interface configuration grouping";
      "IS-IS node tag config state.";
    container lfa node-tags {
      if-feature lfa;
         uses lfa-if-cfg;
         container level-1 node-tag;
      list node-tag {
           uses lfa-if-cfg;
        key tag;
        leaf tag {
          type uint32;
            description
             "LFA level 1 config";
              "Node tag value.";
        }
         container level-2 {
           uses lfa-if-cfg;
        description
             "LFA level 2 config";
          "List of tags.";
      }
      description
           "LFA config";
        "Container for node admin tags.";
    }
  }

  grouping ietf-spf-delay-cfg authentication-global-cfg {
       leaf initial-delay
    choice authentication-type {
         type rt-types:timer-value-milliseconds;
         units msec;
         description
           "Delay used while in QUIET state.";

       }
      case key-chain {
        if-feature key-chain;
        leaf short-delay key-chain {
          type rt-types:timer-value-milliseconds;
         units msec; key-chain:key-chain-ref;
          description
           "Delay used while in SHORT_WAIT state.";
            "Reference to a key-chain.";
        }
      }
      case password {
        leaf long-delay key {
          type rt-types:timer-value-milliseconds;
         units msec; string;
          description
           "Delay used while in LONG_WAIT state.";
            "This leaf specifies the authentication key.";
        }
        leaf hold-down crypto-algorithm {
          type rt-types:timer-value-milliseconds;
         units msec; identityref {
            base key-chain:crypto-algorithm;
          }
          description
           "Timer used to consider an IGP stability period.";
            "Cryptographic algorithm associated with key.";
        }
      }
       leaf time-to-learn {
         type rt-types:timer-value-milliseconds;
         units msec;
      description
           "Duration used to learn all the IGP events
            related to a single component failure."; "Choice of authentication.";
    }
    description "Grouping for IETF SPF delay configuration."; global authentication config.";
  }

  grouping ietf-spf-delay-state metric-type-global-cfg {
    leaf current-state value {
      type enumeration {
        enum "quiet" wide-only {
          description "QUIET state";
            "Advertise new metric style only (RFC5305)";
        }
        enum "short-wait" old-only {
          description "SHORT_WAIT state";
            "Advertise old metric style only (RFC1195)";
        }
        enum "long-wait" both {
          description "LONG_WAIT state"; "Advertise both metric styles";
        }
      }
         config false;
      default wide-only;
      description
           "Current SPF backoff algorithm state.";
        "Type of metric to be generated:
         - wide-only means only new metric style
            is generated,
         - old-only means that only old style metric
           is generated,
         - both means that both are advertised.
         This leaf is only affecting IPv4 metrics.";
    }
       leaf remaining-time-to-learn {
         type rt-types:timer-value-milliseconds;
         units "msec";
         config false;
    description
           "Remaining time until time-to-learn timer fires.";
      "Grouping for global metric style config.";
  }
       leaf remaining-hold-down

  grouping default-metric-global-cfg {
         type rt-types:timer-value-milliseconds;
         units "msec";
         config false;
         description
           "Remaining time until hold-down timer fires.";
       }
    leaf last-event-received value {
      type yang:timestamp;
         config false; wide-metric;
      default "10";
      description
           "Time  "Value of last IGP event received"; the metric";
    }
       leaf next-spf-time {
         type yang:timestamp;
         config false;
    description
           "Time when next SPF has been scheduled.";
      "Global default metric config grouping.";
  }

  grouping overload-global-cfg {
    leaf last-spf-time status {
      type yang:timestamp;
         config boolean;
      default false;
      description
           "Time of last SPF computation.";
        "This leaf specifies the overload status.";
    }
    description "Grouping for IETF SPF delay operational states."; overload bit config.";
  }

  grouping local-rib {
       description "Local-rib grouping.";
       container local-rib {
         config false;
         description "Local-rib.";
         list route {
           key "prefix";
           description "List of IS-IS local RIB Routes";
           leaf prefix {
             type inet:ip-prefix;
             description "Destination prefix.";

           }
           container next-hops {
             description "All next hops for the route.";
             list next-hop overload-max-metric-global-cfg {
               key "next-hop";
               description "List of next hop for the route";
    leaf outgoing-interface timeout {
      type if:interface-ref; rt-types:timer-value-seconds16;
      units "seconds";
      description
                   "Name
        "Timeout (in seconds) of the outgoing interface."; overload condition.";
    }
               leaf next-hop {
                 type inet:ip-address;
    description "Nexthop address.";
               }
             }
           }
           leaf
      "Overload maximum metric {
             type uint32;
             description "Metric for this route."; configuration grouping";
  }

  grouping route-preference-global-cfg {
    choice granularity {
      case detail {
        leaf level internal {
          type level-number; uint8;
          description "Level number
            "Protocol preference for this route."; internal routes.";
        }
        leaf route-tag external {
          type uint32; uint8;
          description "Route tag
            "Protocol preference for this route.";
           }
         } external routes.";
        }
      }

     grouping isis-node-tag-cfg {
       description "IS-IS node tag config.";
       container node-tags {
         if-feature node-tag;
         list node-tag
      case coarse {
           key tag;
        leaf tag default {
          type uint32;
             description
               "Node tag value.";
           } uint8;
          description
             "List of tags.";
            "Protocol preference for all IS-IS routes.";
        }
      }
      description
           "Container
        "Choice for node tags."; implementation of route preference.";
    }
    description
      "Global route preference grouping";
  }

  grouping authentication-global-cfg hello-authentication-cfg {
    choice authentication-type {
      case key-chain {
        if-feature key-chain;
        leaf key-chain {
          type key-chain:key-chain-ref;
          description "Reference to a key-chain.";
        }
      }
      case password {
        leaf key {
          type string;
          description
               "This leaf specifies the authentication key."; "Authentication key specification";
        }
        leaf crypto-algorithm {
          type identityref {
            base key-chain:crypto-algorithm;
          }
          description
            "Cryptographic algorithm associated with key.";
        }
      }
      description "Choice of authentication.";
    }
    description "Grouping for global authentication config."; hello authentication.";
  }

  grouping metric-type-global-cfg hello-interval-cfg {
    leaf value {
      type enumeration rt-types:timer-value-seconds16;
      units "seconds";
      default 10;
      description
        "Interval (in seconds) between successive hello
         messages.";
    }

    description "Interval between hello messages.";
  }

  grouping hello-multiplier-cfg {
           enum wide-only
    leaf value {
      type uint16;
      default 3;
      description
               "Advertise new metric style only (RFC5305)";
        "Number of missed hello messages prior to
         declaring the adjacency down.";
    }
           enum old-only {
    description
               "Advertise old metric style only (RFC1195)";
        "Number of missed hello messages prior to
         adjacency down grouping.";
  }
           enum both

  grouping priority-cfg {
    leaf value {
      type uint8 {
        range "0 .. 127";
      }
      default 64;
      description "Advertise both metricstyles";
        "Priority of interface for DIS election.";
    }

    description "Interface DIS election priority grouping";
  }

  grouping metric-cfg {
    leaf value {
      type wide-metric;
      default wide-only; "10";
      description
           "Type of metric to be generated:
            - wide-only means only new "Metric value.";
    }
    description "Interface metric grouping";
  }
  grouping metric-parameters {
    container metric-type {
      uses metric-type-global-cfg;
      container level-1 {
        uses metric-type-global-cfg;
        description "level-1 specific configuration";
      }
      container level-2 {
        uses metric-type-global-cfg;
        description "level-2 specific configuration";
      }
      description "Metric style
               is generated,
            - old-only means that only old style global configuration";
    }

    container default-metric {
      uses default-metric-global-cfg;
      container level-1 {
        uses default-metric-global-cfg;
        description "level-1 specific configuration";
      }
      container level-2 {
        uses default-metric-global-cfg;
        description "level-2 specific configuration";
      }
      description "Default metric
              is generated,
            - both means that both are advertised.
            This global configuration";
    }
    container auto-cost {
      if-feature auto-cost;
      description
        "Interface Auto-cost configuration state.";
      leaf enable {
        type boolean;
        description
          "Enable/Disable interface auto-cost.";
      }
      leaf reference-bandwidth {
        when "../enable = 'true'" {
          description "Only when auto cost is only affecting IPv4 metrics."; enabled";
        }
        type uint32 {
          range "1..4294967";
        }
        units Mbits;
        description
          "Configure reference bandwidth used to automatically
           determine interface cost (Mbits). The cost is the
           reference bandwidth divided by the interface speed
           with 1 being the minimum cost.";

      }
    }

    description "Grouping for global metric style config."; parameters.";
  }

  grouping default-metric-global-cfg high-availability-parameters {
    container graceful-restart {
      if-feature graceful-restart;
      leaf value enable {
        type wide-metric; boolean;
        default "10"; false;
        description  "Value of the metric"; "Enable graceful restart.";
      }
      leaf restart-interval {
        type rt-types:timer-value-seconds16;
        units "seconds";
        description
         "Global
          "Interval (in seconds) to attempt graceful restart prior
           to failure.";
      }
      leaf helper-enable {
        type boolean;
        default metric config grouping."; true;
        description
          "Enable local IS-IS router as graceful restart helper.";
      }

     grouping overload-global-cfg
      description "Graceful-Restart Configuration.";
    }
    container nsr {
      if-feature nsr;
      description "Non-Stop Routing (NSR) configuration.";
      leaf status enable {
        type boolean;
        default false;
        description
           "This leaf specifies the overload status."; "Enable/Disable Non-Stop Routing (NSR).";
      }
    }
    description "Grouping for overload bit config."; High Availability parameters.";
  }

  grouping overload-max-metric-global-cfg authentication-parameters {
       leaf timeout
    container authentication {
         type rt-types:timer-value-seconds16;
         units "seconds";
      uses authentication-global-cfg;

      container level-1 {
        uses authentication-global-cfg;
        description
           "Timeout (in seconds) of the overload condition."; "level-1 specific configuration";

      }
      container level-2 {
        uses authentication-global-cfg;
        description
         "Overload maximum metric "level-2 specific configuration";
      }
      description "Authentication global configuration grouping"; for
                   both LSPs and SNPs.";
    }
    description "Grouping for authentication parameters";
  }
  grouping route-preference-global-cfg address-family-parameters {
       choice granularity
    container address-families {
         case detail
      if-feature nlpid-control;
      list address-family-list {
        key address-family;
        leaf internal address-family {
          type uint8; iana-rt-types:address-family;
          description
               "Protocol preference for internal routes."; "Address-family";
        }
        leaf external enable {
          type uint8; boolean;
          description
               "Protocol preference for external routes.";
           } "Activate the address family.";
        }
         case coarse {
           leaf default {
             type uint8;
        description
               "Protocol preference for all IS-IS routes.";
           }
          "List of address families and whether or not they
           are activated.";
      }
      description
           "Choice for implementation of route preference."; "Address Family configuration";
    }
    description
         "Global route preference grouping"; "Grouping for address family parameters.";
  }

  grouping hello-authentication-cfg mpls-parameters {
       choice authentication-type
    container mpls {
         case key-chain
      container te-rid {
        if-feature key-chain; te-rid;
        description
          "Stable ISIS Router IP Address used for Traffic
           Engineering";
        leaf key-chain ipv4-router-id {
          type key-chain:key-chain-ref; inet:ipv4-address;
          description "Reference to a key-chain.";
           }
            "Router ID value that would be used in TLV 134.";
        }
         case password {
        leaf key ipv6-router-id {
          type string; inet:ipv6-address;
          description "Authentication key specification";
            "Router ID value that would be used in TLV 140.";

        }
           leaf crypto-algorithm
      }
      container ldp {
             type identityref
        container igp-sync {
               base key-chain:crypto-algorithm;
             }
          if-feature ldp-igp-sync;
          description
               "Cryptographic algorithm associated
            "This container may be augmented with key."; global
             parameters for igp-ldp-sync.";
        }
        description "LDP configuration.";
      }
      description "Choice of authentication."; "MPLS configuration";
    }
    description "Grouping for hello authentication.";
     }

     grouping hello-interval-cfg {
       leaf value {
         type rt-types:timer-value-seconds16;
         units "seconds";
         default 10;
         description
           "Interval (in seconds) between successive hello
            messages.";
       }

       description "Interval between hello messages."; MPLS global parameters.";
  }

  grouping hello-multiplier-cfg lsp-parameters {
    leaf value lsp-mtu {
      type uint16;
      units "bytes";
      default 3;
         description
           "Number of missed hello messages prior to
            declaring the adjacency down.";
       } 1492;
      description
           "Number
        "Maximum size of missed hello messages prior to
            adjacency down grouping."; an LSP PDU in bytes.";
    }

     grouping priority-cfg {
    leaf value lsp-lifetime {
      type uint8 uint16 {
        range "0 .. 127"; "1..65535";
      }
         default 64;
      units "seconds";
      description
           "Priority
        "Lifetime of interface for DIS election.";
       }

       description "Interface DIS election priority grouping"; the router's LSPs in seconds.";
    }

     grouping metric-cfg {
    leaf value lsp-refresh {
      if-feature lsp-refresh;
      type wide-metric;
         default "10";
         description "Metric value.";
       } rt-types:timer-value-seconds16;
      units "seconds";
      description "Interface metric grouping";
        "Refresh interval of the router's LSPs in seconds.";
    }

     grouping lfa-if-cfg {
    leaf candidate-disabled poi-tlv {
      if-feature poi-tlv;
      type boolean;
      default false;
      description
           "Prevent the interface to be used as backup.";
        "Enable advertisement of IS-IS purge TLV.";
    }
    description "Grouping for LSP global parameters.";
  }
  grouping spf-parameters {
    container spf-control {
        leaf enable paths {
          if-feature max-ecmp;
          type boolean;
         default false; uint16 {
            range "1..32";
          }
          description
           "LFA Activation - this model assumes activation
            "Maximum number of per-prefix LFA."; Equal-Cost Multi-Path (ECMP) paths.";
        }
        container remote-lfa ietf-spf-delay {
          if-feature remote-lfa;
         leaf enable {
           type boolean;
           default false; ietf-spf-delay;
          uses ietf-spf-delay;
          description
             "Activates rLFA."; "IETF SPF delay algorithm configuration.";
        }
        description "Remote LFA configuration.";
          "SPF calculation control.";
    }
                description "Grouping for LFA interface configuration"; SPF global parameters.";
  }
  grouping isis-global-cfg instance-config {
    description "IS-IS global configuration grouping";

    uses admin-control;

    leaf level-type {
      type level;
      default "level-all";
      description
        "Level of an IS-IS node - can be level-1-only,
         level-2-only or level-1-2.";
    }

    leaf system-id {
      type system-id;
      description "System-id of the node.";
    }

    leaf maximum-area-addresses {
      if-feature maximum-area-addresses;
      type uint8;
      default 3;
      description "Maximum areas supported.";
    }

    leaf-list area-address {
      type area-address;
      description
        "List of areas supported by the protocol instance.";
    }

    uses lsp-parameters;
    uses high-availability-parameters;
    uses node-tag-config;
    uses metric-parameters;
    uses authentication-parameters;
    uses address-family-parameters;
    uses mpls-parameters;
    uses spf-parameters;
    uses instance-fast-reroute-config;

    container preference {
      uses route-preference-global-cfg;
      description "Router preference configuration for IS-IS
                   protocol instance route installation";
    }

    container mpls overload {
      uses overload-global-cfg;
      description "Router protocol instance overload state
                   configuration";
    }

    container te-rid overload-max-metric {
      if-feature te-rid; overload-max-metric;
      uses overload-max-metric-global-cfg;
      description
             "Stable ISIS Router IP Address used for Traffic
              Engineering";
        "Router protocol instance overload maximum
         metric advertisement configuration.";
    }
  }

  grouping instance-state {
      description
       "IS-IS instance operational state.";
     uses spf-log;
      uses lsp-log;
      uses hostname-db;
      uses lsdb;
      uses local-rib;
      uses system-counters;
      uses instance-fast-reroute-state;
  }

  grouping multi-topology-config {
    description "Per-topology configuration";
    container default-metric {
      uses default-metric-global-cfg;
      container level-1 {
        uses default-metric-global-cfg;
        description "level-1 specific configuration";
      }
      container level-2 {
        uses default-metric-global-cfg;
        description "level-2 specific configuration";
      }
      description "Default metric per-topology configuration";
    }
    uses node-tag-config;
  }

  grouping interface-config {
    description "Interface configuration grouping";
    leaf ipv4-router-id level-type {
      type inet:ipv4-address; level;
      default "level-all";
      description
               "Router ID value that would be used "IS-IS level of the interface.";
    }
    leaf lsp-pacing-interval {
      type rt-types:timer-value-milliseconds;
      units "milliseconds";
      default 33;
      description
        "Interval (in milli-seconds) between LSP
         transmissions.";
    }
    leaf lsp-retransmit-interval {
      type rt-types:timer-value-seconds16;
      units "seconds";
      description
        "Interval (in seconds) between LSP
         retransmissions.";
    }
    leaf passive {
      type boolean;
      default "false";
      description
        "Indicates whetherthe interface is in TLV 134."; passive mode (IS-IS
         not running but network is advertised).";
    }
    leaf ipv6-router-id csnp-interval {
      type inet:ipv6-address; rt-types:timer-value-seconds16;
      units "seconds";
      default 10;
      description
               "Router ID value that would be used in TLV 140.";
           }
         "Interval (in seconds) between CSNP messages.";
    }
    container ldp hello-padding {
           container igp-sync
      leaf enable {
             if-feature ldp-igp-sync;
        type boolean;
        default "true";
        description
               "This container may be augmented with global
                parameters for igp-ldp-sync.";
          "IS-IS Hello-padding activation - enabled by default.";
      }
      description "LDP "IS-IS hello padding configuration.";
    }
         description "MPLS configuration";
       }
       container auto-cost {
         if-feature auto-cost;
    leaf reference-bandwidth mesh-group-enable {
      type uint32;
           units "bps"; mesh-group-state;
      description "Bandwidth for calculating metric."; "IS-IS interface mesh-group state";
    }
    leaf enable mesh-group {
      when "../mesh-group-enable = 'mesh-set'" {
           type boolean;
           default false;
        description "Enable/disable auto-cost.";
          "Only valid when mesh-group-enable equals meshset";
      }
      type uint8;
      description "Auto-cost configuration."; "IS-IS interface mesh-group ID.";
    }
    leaf lsp-mtu interface-type {
      type uint16;
         units "bytes"; interface-type;
      default 1492; "broadcast";
      description
           "Maximum size
        "Type of an LSP PDU in bytes."; adjacency to be established on the interface. This
         dictates the type of hello messages that are used.";
    }
       leaf lsp-lifetime

    uses admin-control;

    leaf-list tag {
      if-feature prefix-tag;
      type uint16 {
           range "1..65535";
         }
         units "seconds"; uint32;
      description
           "Lifetime
        "List of tags associated with the router's LSPs in seconds."; interface.";
    }
       leaf lsp-refresh
    leaf-list tag64 {
      if-feature lsp-refresh; prefix-tag64;
      type rt-types:timer-value-seconds16;
         units "seconds"; uint64;
      description
           "Refresh interval
        "List of 64-bit tags associated with the router's LSPs in seconds."; interface.";
    }
       container graceful-restart {
         if-feature graceful-restart;
    leaf enable node-flag {
      if-feature node-flag;
      type boolean;
      default false;
      description "Enable graceful restart.";
        "Set prefix as a node representative prefix.";
    }
         leaf restart-interval
    container hello-authentication {
           type rt-types:timer-value-seconds16;
           units "seconds";
      uses hello-authentication-cfg;
      container level-1 {
        uses hello-authentication-cfg;
        description
             "Interval (in seconds) to attempt graceful restart prior "level-1 specific configuration";
      }
      container level-2 {
        uses hello-authentication-cfg;
        description "level-2 specific configuration";
      }
      description
        "Authentication type to failure."; be used in hello messages.";
    }
    container hello-interval {
      uses hello-interval-cfg;
      container level-1 {
        uses hello-interval-cfg;
        description "level-1 specific configuration";
      }
         leaf helper-enable
      container level-2 {
           type boolean;
           default true;
        uses hello-interval-cfg;
        description
             "Enable local IS-IS router as graceful restart helper."; "level-2 specific configuration";
      }
      description "Graceful-Restart Configuration."; "Interval between hello messages.";
    }
    container nsr hello-multiplier {
         if-feature nsr;
      uses hello-multiplier-cfg;
      container level-1 {
        uses hello-multiplier-cfg;
        description "Non-Stop Routing (NSR) configuration.";
         leaf enable "level-1 specific configuration";
      }
      container level-2 {
           type boolean;
           default false;
        uses hello-multiplier-cfg;
        description "Enable/Disable Non-Stop Routing (NSR)."; "level-2 specific configuration";
      }
      description "Hello multiplier configuration.";
    }

       uses isis-node-tag-cfg;
    container authentication priority {
      must '../interface-type = "broadcast"' {
        error-message
          "Priority only applies to broadcast interfaces.";
        description "Check for broadcast interface.";
      }
      uses authentication-global-cfg; priority-cfg;
      container level-1 {
        uses authentication-global-cfg; priority-cfg;
        description "level-1 specific configuration";
      }
      container level-2 {
        uses authentication-global-cfg; priority-cfg;
        description "level-2 specific configuration";
      }
      description "Authentication global configuration "Priority for
                      both LSPs and SNPs."; DIS election.";
    }
    container metric-type metric {
      uses metric-type-global-cfg; metric-cfg;
      container level-1 {
        uses metric-type-global-cfg; metric-cfg;
        description "level-1 specific configuration";
      }
      container level-2 {
        uses metric-type-global-cfg; metric-cfg;
        description "level-2 specific configuration";
      }
      description "Metric style global configuration"; configuration.";
    }
    container default-metric bfd {
      if-feature bfd;
      description "BFD Client Configuration.";
      uses default-metric-global-cfg; bfd-types:client-cfg-parms;

      reference "draft-ietf-bfd-yang-xx.txt:
                 YANG Data Model for Bidirectional Forwarding
                 Detection (BFD)";
    }
    container address-families {
      if-feature nlpid-control;
      list address-family-list {
        key address-family;
        leaf address-family {
          type iana-rt-types:address-family;
          description  "Address-family";
        }
        description "List of AFs.";
      }
      description "Interface address-families";
    }
    container mpls {
      container ldp {
        leaf igp-sync {
          if-feature ldp-igp-sync;
          type boolean;
          default false;
          description "Enables IGP/LDP synchronization";
        }
        description "LDP protocol related configuration.";
      }
      description "MPLS configuration for IS-IS interfaces";
    }
    uses interface-fast-reroute-config;
  }

  grouping multi-topology-interface-config {
    description "IS-IS interface topology configuration.";
    container metric {
      uses metric-cfg;
      container level-1 {
        uses default-metric-global-cfg; metric-cfg;
        description "level-1 specific configuration";
      }
      container level-2 {
        uses default-metric-global-cfg; metric-cfg;
        description "level-2 specific configuration";
      }
      description "Default metric global configuration"; "Metric IS-IS interface configuration.";
    }
  }
  grouping interface-state {
    description
      "IS-IS interface operational state.";
    uses adjacency-state;
    uses event-counters;
    uses packet-counters;
  }

 /* Grouping for the hostname database */

  grouping hostname-db {
    container afs hostnames {
         if-feature nlpid-control;
      config false;
      list af hostname {
        key af; system-id;
        leaf af system-id {
          type iana-rt-types:address-family; system-id;
          description "Address-family";
            "System-id associated with the hostname.";
        }
        leaf enable hostname {
          type boolean; string;
          description "Activate
            "Hostname associated with the address family."; system ID.";
        }
        description
          "List of address families and whether or not they
              are activated."; system-id/hostname associations.";
      }
      description "Address Family configuration";
        "Hostname to system-id mapping database.";
    }

       container preference {
         uses route-preference-global-cfg;
    description "Router preference configuration
      "Grouping for IS-IS
                      protocol instance route installation"; hostname to system-id mapping database.";
  }

  /* Groupings for counters */

  grouping system-counters {
    container overload system-counters {
         uses overload-global-cfg;
      config false;
      list level {
        key level;

        leaf level {
          type level-number;
          description "Router protocol instance overload state
                      configuration"; "IS-IS level.";
        }

       container overload-max-metric
        leaf corrupted-lsps {
         if-feature overload-max-metric;
         uses overload-max-metric-global-cfg;
          type uint32;
          description
           "Router protocol instance overload maximum
            metric advertisement configuration.";
       }
            "Number of corrupted in-memory LSPs detected.
             LSPs received from the wire with a bad
             checksum are silently dropped and not counted.
             LSPs received from the wire with parse errors
             are counted by lsp-errors.";
        }

     grouping isis-global-topologies-cfg
        leaf authentication-type-fails {
          type uint32;
          description "Per-topology configuration";
       container default-metric {
         uses default-metric-global-cfg;
         container level-1
             "Number of authentication type mismatches.";
        }
        leaf authentication-fails {
           uses default-metric-global-cfg;
          type uint32;
          description "level-1 specific configuration";
            "Number of authentication key failures.";
        }
         container level-2
        leaf database-overload {
           uses default-metric-global-cfg;
          type uint32;
          description "level-2 specific configuration";
            "Number of times the database has become
             overloaded.";
        }
        leaf own-lsp-purge {
          type uint32;
          description "Default metric per-topology configuration";
       }
       uses isis-node-tag-cfg;
            "Number of times a zero-aged copy of the system's
             own LSP is received from some other IS-IS node.";
        }

     grouping isis-if-cfg
        leaf manual-address-drop-from-area {
          type uint32;
          description "Interface configuration grouping";
            "Number of times a manual address
             has been dropped from the area.";
        }
        leaf level-type max-sequence {
          type level;
         default "level-all"; uint32;
          description "IS-IS level
            "Number of times the interface."; system has attempted
             to exceed the maximum sequence number.";
        }
        leaf lsp-pacing-interval sequence-number-skipped {
          type rt-types:timer-value-milliseconds;
         units "milliseconds";
         default 33; uint32;
          description
           "Interval (in milli-seconds) between LSP
            transmissions.";
            "Number of times a sequence number skip has
             occured.";
        }
        leaf lsp-retransmit-interval id-len-mismatch {
          type rt-types:timer-value-seconds16;
         units "seconds"; uint32;
          description
           "Interval (in seconds) between LSP
            retransmissions.";
            "Number of times a PDU is received with a
             different value for the ID field length
             than that of the receiving system.";
        }
        leaf passive partition-changes {
          type boolean;
         default "false"; uint32;
          description
           "Indicates whetherthe interface is in passive mode (IS-IS
            not running but network is advertised).";
            "Number of partition changes detected.";
        }
        leaf csnp-interval lsp-errors {
          type rt-types:timer-value-seconds16;
         units "seconds";
         default 10; uint32;
          description
            "Interval (in seconds) between CSNP messages.";
            "Number of LSPs with errors we have received.";
        }
       container hello-padding {
        leaf enable spf-runs {
          type boolean;
           default "true"; uint32;
          description
             "IS-IS Hello-padding activation - enabled by default.";
            "Number of times we ran SPF at this level.";
        }
        description "IS-IS hello padding configuration.";
          "List of supported levels.";
      }
      description
        "List counters for the IS-IS protocol instance";
    }
    description "System counters grouping.";
  }

  grouping event-counters {
    container event-counters {
      config false;
      leaf mesh-group-enable adjacency-changes {
        type mesh-group-state; uint32;
        description "IS-IS interface mesh-group state";
          "The number of times an adjacency state change has
           occured on this interface.";
      }
      leaf mesh-group {
         when "../mesh-group-enable = 'mesh-set'" adjacency-number {
        type uint32;
        description
             "Only valid when mesh-group-enable equals meshset";
          "The number of adjacencies on this interface.";
      }
      leaf init-fails {
        type uint8; uint32;
        description "IS-IS
          "The number of times initialization of this
           interface mesh-group ID."; has failed. This counts events such
           as PPP NCP failures. Failures to form an
           adjacency are counted by adjacency-rejects.";
      }
      leaf interface-type adjacency-rejects {
        type interface-type;
         default "broadcast"; uint32;
        description
           "Type
          "The number of times an adjacency to be established has been
           rejected on the interface. This
            dictates the type of hello messages that are used."; this interface.";
      }

       uses admin-control;

       leaf-list tag
      leaf id-len-mismatch {
         if-feature prefix-tag;
        type uint32;
        description
           "List
          "The number of tags associated times an IS-IS PDU with the an ID
           field length different from that for this
           system has been received on this interface.";
      }
       leaf-list tag64
      leaf max-area-addresses-mismatch {
         if-feature prefix-tag64;
        type uint64; uint32;
        description
           "List
          "The number of 64-bit tags associated times an IS-IS PDU has been
           received on this interface with the interface.";
           max area address field differing from that of
           this system.";
      }
      leaf node-flag authentication-type-fails {
         if-feature node-flag;
        type boolean;
         default false;
         description
           "Set prefix as a node representative prefix.";
       }
       container hello-authentication {
         uses hello-authentication-cfg;
         container level-1 {
           uses hello-authentication-cfg;
           description "level-1 specific configuration";
         }
         container level-2 {
           uses hello-authentication-cfg;
           description "level-2 specific configuration";
         } uint32;
        description
           "Authentication
          "Number of authentication type to be used in hello messages.";
       }
       container hello-interval {
         uses hello-interval-cfg;
         container level-1 {
           uses hello-interval-cfg;
           description "level-1 specific configuration";
         }
         container level-2 {
           uses hello-interval-cfg;
           description "level-2 specific configuration";
         }
         description "Interval between hello messages.";
       }
       container hello-multiplier {
         uses hello-multiplier-cfg;
         container level-1 {
           uses hello-multiplier-cfg;
           description "level-1 specific configuration";
         }
         container level-2 {
           uses hello-multiplier-cfg;
           description "level-2 specific configuration";
         }
         description "Hello multiplier configuration."; mismatches.";
      }
       container priority {
         must '../interface-type = "broadcast"'
      leaf authentication-fails {
           error-message
             "Priority only applies to broadcast interfaces.";
        type uint32;
        description "Check for broadcast interface.";
          "Number of authentication key failures.";
      }
         uses priority-cfg;
         container level-1
      leaf lan-dis-changes {
           uses priority-cfg;
        type uint32;
        description "level-1 specific configuration";
          "The number of times the DIS has changed on this
           interface at this level. If the interface type is
           point-to-point,the count is zero.";
      }
         container level-2 {
           uses priority-cfg;
      description "level-2 specific configuration"; "IS-IS interface event counters.";
    }
    description "Priority
      "Grouping for DIS election."; IS-IS interface event counters";
  }
       container metric

  grouping packet-counters {
         uses metric-cfg;
    container level-1 packet-counters {
           uses metric-cfg;
      config false;
      list level {
        key level;

        leaf level {
          type level-number;
          description "level-1 specific configuration"; "IS-IS level.";
        }
        container level-2 iih {
           uses metric-cfg;
          leaf in {
            type uint32;
            description "level-2 specific configuration"; "Received IIH PDUs.";
          }
          leaf out {
            type uint32;
            description "Metric configuration."; "Sent IIH PDUs.";
          }
       container bfd {
         if-feature bfd;
          description "BFD Client Configuration.";
         uses bfd-types:client-cfg-parms;

         reference "draft-ietf-bfd-yang-xx.txt:
                    YANG Data Model for Bidirectional Forwarding
                    Detection (BFD)"; "Number of IIH PDUs received/sent.";
        }
        container afs {
         if-feature nlpid-control;
         list af ish {
           key af;
          leaf af in {
            type iana-rt-types:address-family; uint32;
            description  "Address-family"; "Received ISH PDUs.";
          }
          leaf out {
            type uint32;
            description "List of AFs."; "Sent ISH PDUs.";
          }
          description "Interface address-families";
            "ISH PDUs received/sent.";
        }
        container mpls {
         container ldp esh {
          leaf igp-sync in {
             if-feature ldp-igp-sync;
            type boolean;
             default false; uint32;
            description "Enables IGP/LDP synchronization"; "Received ESH PDUs.";
          }
          leaf out {
            type uint32;
            description "LDP protocol related configuration."; "Sent ESH PDUs.";
          }
          description "MPLS configuration for IS-IS interfaces";
       } "Number of ESH PDUs received/sent.";
        }

     grouping isis-if-topologies-cfg {
       description "IS-IS interface topology configuration.";
        container metric lsp {
         uses metric-cfg;
         container level-1
          leaf in {
           uses metric-cfg;
            type uint32;
            description "level-1 specific configuration"; "Received LSP PDUs.";
          }
         container level-2
          leaf out {
           uses metric-cfg;
            type uint32;
            description "level-2 specific configuration"; "Sent LSP PDUs.";
          }
          description "Metric IS-IS interface configuration.";
       } "Number of LSP PDUs received/sent.";
        }

     grouping system-counters {
        container system-counters {
         config false;
         list level psnp {
           key level;
          leaf level in {
            type level-number; uint32;
            description "IS-IS level."; "Received PSNP PDUs.";
          }
          leaf corrupted-lsps out {
            type uint32;
            description "Sent PSNP PDUs.";
          }
          description "Number of corrupted in-memory LSPs detected.
                LSPs received from the wire with a bad
                checksum are silently dropped and not counted.

                LSPs received from the wire with parse errors
                are counted by lsp-errors."; PSNP PDUs received/sent.";
        }
        container csnp {
          leaf authentication-type-fails in {
            type uint32;
            description
                "Number of authentication type mismatches."; "Received CSNP PDUs.";
          }
          leaf authentication-fails out {
            type uint32;
            description "Sent CSNP PDUs.";
          }
          description "Number of authentication key failures."; CSNP PDUs received/sent.";
        }
        container unknown {
          leaf database-overload in {
            type uint32;
            description
               "Number of times the database has become
                overloaded."; "Received unknown PDUs.";
          }
          leaf own-lsp-purge out {
            type uint32;
            description "Sent unknown PDUs.";
          }
          description "Number of times a zero-aged copy unknown PDUs received/sent.";
        }
        description
          "List of the system's
                own LSP is received from some other packet counter for supported llevels.";
      }
      description "Packet counters per IS-IS node."; level.";
    }
    description
      "Grouping for per IS-IS Level packet counters.";
  }

        /* Groupings for various log buffers */
  grouping spf-log {
    container spf-log {
      config false;
      list event {
        key id;

        leaf manual-address-drop-from-area id {
          type uint32;
          description
               "Number of times a manual address
                has been dropped from the area.";
            "Event identifier -  purely internal value.";
        }
        leaf max-sequence spf-type {
          type uint32; enumeration {
            enum full {
              description
               "Number "Full SPF computation.";
            }
            enum route-only {
              description
                "Route reachability only SPF computation";

            }
          }
          description "Type of times the system has attempted
                to exceed the maximum sequence number."; SPF computation performed.";
        }
        leaf sequence-number-skipped level {
          type uint32; level-number;
          description
               "Number of times a sequence
            "IS-IS level number skip has
                occured."; for SPF computation";
        }
        leaf id-len-mismatch schedule-timestamp {
          type uint32; yang:timestamp;
          description
               "Number
            "Timestamp of times a PDU is received with a
                different value for when the ID field length
                than that SPF computation was
             scheduled.";
        }
        leaf start-timestamp {
          type yang:timestamp;
          description
            "Timestamp of when the receiving system."; SPF computation started.";
        }
        leaf partition-changes end-timestamp {
          type uint32; yang:timestamp;
          description
               "Number
            "Timestamp of partition changes detected."; when the SPF computation ended.";
        }
        list trigger-lsp {
          key "lsp";
          leaf lsp-errors lsp {
            type uint32; lsp-id;
            description
               "Number
              "LSPID of LSPs with errors we have received."; the LSP triggering SPF computation.";
          }
          leaf spf-runs sequence {
            type uint32;
            description
               "Number
              "Sequence number of times we ran the LSP triggering SPF at this level.";
               computation";
          }
          description
            "This list includes the LSPs that triggered the
             SPF computation.";
        }
        description
          "List of supported levels."; computation events - implemented as a
           wrapping buffer.";
      }

      description
           "List counters for
        "This container lists the IS-IS protocol instance"; SPF computation events.";
    }
    description "System counters grouping."; "Grouping for spf-log events.";
  }

  grouping event-counters lsp-log {
    container event-counters lsp-log {
      config false;
      list event {
        key id;

        leaf adjacency-changes id {
          type uint32;
          description
             "The number of times an adjacency state change has
              occured on this interface.";
            "Event identifier -  purely internal value.";
        }
        leaf adjacency-number level {
          type uint32; level-number;
          description
             "The
            "IS-IS level number of adjacencies on this interface."; for LSP";
        }
        container lsp {
          leaf init-fails lsp {
            type uint32; lsp-id;
            description
             "The number of times initialization
              "LSPID of this
              interface has failed. This counts events such
              as PPP NCP failures. Failures to form an
              adjacency are counted by adjacency-rejects."; the LSP.";
          }
          leaf adjacency-rejects sequence {
            type uint32;
            description
             "The
              "Sequence number of times an adjacency has been
              rejected on this interface."; the LSP.";
          }
          description
            "LSP identification container - either the received
             LSP or the locally generated LSP.";
        }

        leaf id-len-mismatch received-timestamp {
          type uint32; yang:timestamp;
          description
             "The number
            "This is the timestamp when the LSA was received.
             In case of times an IS-IS PDU with an ID
              field length different from that for this
              system has been received on this interface."; local LSA update, the timestamp refers
             to the LSA origination time.";
        }

        leaf max-area-addresses-mismatch reason {
          type uint32; identityref {
            base lsp-log-reason;

          }
          description
             "The number "Type of times an IS-IS PDU has been
              received on this interface with the
              max area address field differing from that LSP change.";
        }

        description
          "List of
              this system."; LSP events - implemented as a
           wrapping buffer.";
      }

      description
        "This container lists the LSP log.
         Local LSP modifications are also included
         in the list.";

    } description "Grouping for LSP log.";
  }

  /* Groupings for the LSDB description */

  /* Unknown TLV and subTLV description */
  grouping tlv {
    description
      "Type-Length-Value (TLV)";
    leaf authentication-type-fails type {
      type uint32; uint16;
      description
             "Number of authentication type mismatches."; "TLV type.";
    }
    leaf authentication-fails length {
      type uint32; uint16;
      description
             "Number of authentication key failures."; "TLV length (octets).";
    }
    leaf lan-dis-changes value {
      type uint32;
           description
             "The number of times the DIS has changed on this
              interface at this level. If the interface type is
              point-to-point,the count is zero.";
         } yang:hex-string;
      description "IS-IS interface event counters."; "TLV value.";
    }
       description
         "Grouping for IS-IS interface event counters";
  }

  grouping packet-counters unknown-tlvs {
    description
      "Unknown TLVs grouping - Used for unknown TLVs or
       unknown sub-TLVs.";
    container packet-counters unknown-tlvs {
         config false;
      description "All unknown TLVs.";
      list level unknown-tlv {
           key level;
        description "Unknown TLV.";
        uses tlv;

      }
    }
  }

  /* TLVs and subTLVs for prefixes */

  grouping prefix-reachability-attributes {
    description
      "Grouping for extended reachability attributes of an
       IPv4 or IPv6 prefix.";

    leaf level external-prefix-flag {
      type level-number; boolean;
      description "IS-IS level."; "External prefix flag.";
    }
           container iih {
    leaf in readvertisement-flag {
      type uint32; boolean;
      description "Received IIH PDUs."; "Readvertisement flag.";
    }
    leaf out node-flag {
      type uint32; boolean;
      description "Sent IIH PDUs."; "Node flag.";
    }
             description "Number of IIH PDUs received/sent.";
  }
           container ish

  grouping prefix-ipv4-source-router-id {
    description
      "Grouping for the IPv4 source router ID of a prefix
       advertisement.";

    leaf in ipv4-source-router-id {
      type uint32; inet:ipv4-address;
      description "Received ISH PDUs."; "IPv4 Source router ID address.";
    }
  }

  grouping prefix-ipv6-source-router-id {
    description
      "Grouping for the IPv6 source router ID of a prefix
       advertisement.";

    leaf out ipv6-source-router-id {
      type uint32; inet:ipv6-address;
      description "Sent ISH PDUs."; "IPv6 Source router ID address.";
    }
  }

  grouping prefix-attributes-extension {
    description
               "ISH PDUs received/sent."; "Prefix extended attributes.";

    uses prefix-reachability-attributes;
    uses prefix-ipv4-source-router-id;
    uses prefix-ipv6-source-router-id;
  }
           container esh

  grouping prefix-ipv4-std {
    description
      "Grouping for attributes of an IPv4 standard prefix.";
    leaf in up-down {
      type uint32; boolean;
      description "Received ESH PDUs."; "Value of up/down bit.";
    }
    leaf out i-e {
      type uint32;
               description "Sent ESH PDUs.";
             } boolean;
      description "Number "Value of ESH PDUs received/sent."; I/E bit.";
    }
           container lsp {
    leaf in ip-prefix {
      type uint32; inet:ipv4-address;
      description "Received LSP PDUs."; "IPv4 prefix address";
    }
    leaf out prefix-len {
      type uint32; uint8;
      description "Sent LSP PDUs."; "IPv4 prefix length (in bits)";
    }
    leaf default-metric {
      type std-metric;
      description "Number of LSP PDUs received/sent."; "Default IS-IS metric for IPv4 prefix";
    }
    container psnp delay-metric {
      leaf in metric {
        type uint32; std-metric;
        description "Received PSNP PDUs."; "IS-IS delay metric for IPv4 prefix";
      }
      leaf out supported {
        type uint32; boolean;
        default "false";
        description "Sent PSNP PDUs.";
          "Indicates whether IS-IS delay metric is supported.";
      }
      description "Number of PSNP PDUs received/sent."; "IS-IS delay metric container.";
    }
    container csnp expense-metric {
      leaf in metric {
        type uint32; std-metric;
        description "Received CSNP PDUs."; "IS-IS expense metric for IPv4 prefix";
      }
      leaf out supported {
        type uint32; boolean;
        default "false";
        description "Sent CSNP PDUs.";
          "Indicates whether IS-IS delay metric is supported.";
      }
      description "Number of CSNP PDUs received/sent."; "IS-IS expense metric container.";
    }
    container unknown error-metric {
      leaf in metric {
        type uint32; std-metric;
        description "Received unknown PDUs.";
          "This leaf describes the IS-IS error metric value";
      }
      leaf out supported {
        type uint32;
               description "Sent unknown PDUs.";
             }
             description "Number of unknown PDUs received/sent.";
           } boolean;
        default "false";
        description
             "List of packet counter "IS-IS error metric for supported llevels."; IPv4 prefix";
      }
      description "Packet counters per IS-IS level."; "IS-IS error metric container.";
    }
       description
         "Grouping for per IS-IS Level packet counters.";
  }

  grouping spf-log {
       container spf-log {
         config false;
         list event prefix-ipv4-extended {
           key id;
    description
      "Grouping for attributes of an IPv4 extended prefix.";
    leaf id up-down {
      type uint32; boolean;
      description
               "Event identifier -  purely internal value.";  "Value of up/down bit.";
    }
    leaf spf-type ip-prefix {
      type enumeration {
               enum full { inet:ipv4-address;
      description "Full SPF computation."; "IPv4 prefix address";
    }
               enum route-only
    leaf prefix-len {
      type uint8;
      description
                   "Route reachability only SPF computation";
               }
             }
             description "Type of SPF computation performed."; "IPv4 prefix length (in bits)";
    }

    leaf level metric {
      type level-number; wide-metric;
      description "IS-IS level number for SPF computation"; wide metric value";
    }
           leaf schedule-timestamp
    leaf-list tag {
      type yang:timestamp; uint32;
      description
               "Timestamp
        "List of when 32-bit tags associated with the SPF computation was
                scheduled."; IPv4 prefix.";
    }
           leaf start-timestamp
    leaf-list tag64 {
      type yang:timestamp; uint64;
      description
               "Timestamp
        "List of when 32-bit tags associated with the SPF computation started."; IPv4 prefix.";
    }
    uses prefix-attributes-extension;
  }

  grouping prefix-ipv6-extended {
    description "Grouping for attributes of an IPv6 prefix.";
    leaf end-timestamp up-down {
      type yang:timestamp; boolean;
      description
               "Timestamp "Value of when the SPF computation ended."; up/down bit.";
    }
           list trigger-lsp {
             key "lsp";
    leaf lsp ip-prefix {
      type lsp-id; inet:ipv6-address;
      description
                 "LSPID of the LSP triggering SPF computation."; "IPv6 prefix address";
    }
    leaf sequence prefix-len {
      type uint32; uint8;
      description
                 "Sequence number of the LSP triggering SPF
                  computation";  "IPv4 prefix length (in bits)";
    }
    leaf metric {
      type wide-metric;
      description
               "This list includes the LSPs that triggered the
                SPF computation.";  "IS-IS wide metric value";
    }
    leaf-list tag {
      type uint32;
      description
        "List of computation events - implemented as a
              wrapping buffer."; 32-bit tags associated with the IPv4 prefix.";
    }
    leaf-list tag64 {
      type uint64;
      description
           "This container lists
        "List of 32-bit tags associated with the SPF computation events."; IPv4 prefix.";
    }
    uses prefix-attributes-extension;
  }
       description "Grouping

        /* TLVs and subTLVs for spf-log events.";
     } neighbors */

        grouping lsp-log {
       container lsp-log {
         config false;
         list event {
           key id;

           leaf id neighbor-link-attributes {
             type uint32;
                description
               "Event identifier -  purely internal value.";
           }
                        "Grouping for link attributes as defined
                        in RFC5029";
                leaf level link-attributes-flags {
                        type level-number; uint16;
                        description
               "IS-IS level number
                                "Flags for LSP"; the link attributes";
                }
           container lsp
        }
        grouping neighbor-gmpls-extensions {
                description
                        "Grouping for GMPLS attributes of a neighbor as
defined
                        in RFC5307";
                leaf lsp link-local-id {
                        type lsp-id; uint32;
                        description
                 "LSPID
                                "Local identifier of the LSP."; link.";
                }
                leaf sequence remote-local-id {
                        type uint32;
                        description
                 "Sequence number
                                "Remote identifier of the LSP.";

             }
             description
               "LSP identification container - either the received
                LSP or the locally generated LSP."; link.";
                }
                leaf received-timestamp protection-capability {
                        type yang:timestamp; uint8;
                        description
               "Timestamp
                                "Describes the protection capabilities
                                of when the LSP was received. In case link. This is the value of local LSP update, the timestamp refers to
                                first octet of the
                local LSP update time."; sub-TLV type 20
value.";
                }
                container interface-switching-capability {
                        description
                                "Interface switching capabilities of
the link.";
                        leaf change switching-capability {
                                type identityref {
               base lsp-log-reason;
             } uint8;
                                description "Type
                                        "Switching capability of LSP change."; the
link.";
                        }
                        leaf encoding {
                                type uint8;
                                description
             "List
                                        "Type of encoding of the LSP events - implemented as a
              wrapping buffer.";
         }

         description
           "LSP reception and local LSP origination events
            container.";

       }
       description "Grouping for LSP log.";
being used.";
                        }

     grouping hostname-db {
                        container hostnames max-lsp-bandwidths {
         config false;
                                description "Per priority max LSP
bandwidths.";
                                list hostname {
           key system-id;
           leaf system-id max-lsp-bandwidth {
             type system-id;
             description
               "System-id associated with the hostname.";
           }
                                        leaf hostname priority {
                                                type string;
             description
               "Hostname associated with the system ID.";
           }
           description
             "List of system-id/hostname associations.";
         }
         description
           "Hostname to system-id mapping database.";
       }
       description
         "Grouping for hostname to system-id mapping database.";
     }

     /* Groupings for the LSDB description */

     grouping prefix-reachability-attributes uint8 {
       description
         "Grouping for extended reachability attributes of an
          IPv4 or IPv6 prefix.";
                                                        range "0 .. 7";
                                                }
                                                description "Priority
from 0 to 7.";
                                        }
                                        leaf external-prefix-flag bandwidth {
                                                type boolean;
rt-types:bandwidth-ieee-float32;
                                                description "External prefix flag."; "max LSP
bandwidth.";
                                        }
                                        description
                                                "List of max LSP
bandwidths for different
                                                 priorities.";
                                }
                        }
                        container tdm-specific {
                                when "switching-capability = 100";
                                description
                                        "Switching Capability-specific
information applicable
                                        when switching type is TDM.";

                                leaf readvertisement-flag minimum-lsp-bandwidth {
                                        type boolean;
rt-types:bandwidth-ieee-float32;
                                        description "Readvertisement flag."; "minimum LSP
bandwidth.";
                                }
                                leaf node-flag indication {
                                        type boolean; uint8;
                                        description "Node flag.";
                                                "The indication whether
the interface supports Standard or Arbitrary
                                                SONET/SDH.";
                                }
                        }

     grouping prefix-ipv4-source-router-id
                        container psc-specific {
                                when "switching-capability >= 1 and
switching-capability <= 4";
                                description
         "Grouping for the IPv4 source router ID of a prefix
          advertisement.";
                                        "Switching Capability-specific
information applicable
                                        when switching type is
PSC1,PSC2,PSC3 or PSC4.";

                                leaf ipv4-source-router-id minimum-lsp-bandwidth {
                                        type inet:ipv4-address;
rt-types:bandwidth-ieee-float32;
                                        description "IPv4 Source router ID address."; "minimum LSP
bandwidth.";
                                }
                                leaf mtu {
                                        type uint16;
                                        units bytes;
                                        description
                                                "Interface MTU";
                                }
                        }
                }
        }

        grouping prefix-ipv6-source-router-id neighbor-extended-te-extensions {
                description
                        "Grouping for the IPv6 source router ID TE attributes of a prefix
          advertisement."; neighbor as
defined
                        in RFC7810";

                container unidirectional-link-delay {
                        description
                                "Container for the average delay
                                from the local neighbor to the remote
one.";
                        leaf ipv6-source-router-id flags {
                                type inet:ipv6-address; bits {
                                        bit A {
                                                position 7;
                                                description "IPv6 Source router ID address.";
                                                        "The A bit
represents the Anomalous (A) bit.
                                                        The A bit is
set when the measured value of
                                                        this parameter
exceeds its configured
                                                        maximum
threshold.
                                                        The A bit is
cleared when the measured value
                                                        falls below its
configured reuse threshold.
                                                        If the A bit is
clear,
                                                        the value
represents steady-state link performance.";
                                        }
                                }

     grouping prefix-attributes-extension
                                description
                                        "Flags.";
                        }
                        leaf value {
                                type uint32;
                                units usec;
                                description "Prefix extended attributes.";

       uses prefix-reachability-attributes;
       uses prefix-ipv4-source-router-id;
       uses prefix-ipv6-source-router-id;
                                        "Delay value expressed in
microseconds.";
                        }

     grouping prefix-ipv4-std
                }
                container min-max-unidirectional-link-delay {
                        description
         "Grouping
                                "Container for attributes of an IPv4 standard prefix."; the min and max delay
                                from the local neighbor to the remote
one.";
                        leaf up-down flags {
                                type boolean; bits {
                                        bit A {
                                                position 7;
                                                description
                                                        "The A bit
represents the Anomalous (A) bit.
                                                        The A bit is
set when the measured value of
                                                        this parameter
exceeds its configured
                                                        maximum
threshold.
                                                        The A bit is
cleared when the measured value
                                                        falls below its
configured reuse threshold.
                                                        If the A bit is
clear,
                                                        the value
represents steady-state link performance.";
                                        }
                                }
                                description "Value of up/down bit.";
                                        "Flags.";
                        }
                        leaf i-e min-value {
                                type boolean; uint32;
                                units usec;
                                description "Value of I/E bit.";
                                        "Minimum delay value expressed
in microseconds.";
                        }
                        leaf ip-prefix max-value {
                                type inet:ipv4-address; uint32;
                                units usec;
                                description "IPv4 prefix address";
                                        "Maximum delay value expressed
in microseconds.";
                        }
       leaf prefix-len
                }
                container unidirectional-link-delay-variation {
         type uint8;
                        description "IPv4 prefix length (in bits)";
       }
                                "Container for the average delay
variation
                                from the local neighbor to the remote
one.";
                        leaf default-metric value {
                                type std-metric; uint32;
                                units usec;
                                description "Default IS-IS metric for IPv4 prefix";
                                        "Delay variation value
expressed in microseconds.";
                        }
                }
                container delay-metric {
         leaf metric {
           type std-metric; unidirectional-link-loss{
                        description "IS-IS delay metric
                                "Container for IPv4 prefix";
         } the packet loss
                                from the local neighbor to the remote
one.";
                        leaf supported flags {
                                type boolean;
           default "false"; bits {
                                        bit A {
                                                position 7;
                                                description
             "Indicates whether IS-IS delay metric
                                                        "The A bit
represents the Anomalous (A) bit.
                                                        The A bit is supported.";
set when the measured value of
                                                        this parameter
exceeds its configured
                                                        maximum
threshold.
                                                        The A bit is
cleared when the measured value
                                                        falls below its
configured reuse threshold.
                                                        If the A bit is
clear,
                                                        the value
represents steady-state link performance.";
                                        }
                                }
                                description "IS-IS delay metric container.";
                                        "Flags.";

                        }
       container expense-metric {
                        leaf metric value {
                                type std-metric; uint32;
                                units percent;
                                description "IS-IS expense metric for IPv4 prefix";
                                        "Link packet loss expressed as
a percentage
                                        of the total traffic sent over
a configurable interval.";
                        }
                }
                container unidirectional-link-residual-bandwidth {
                        description
                                "Container for the residual bandwidth
                                from the local neighbor to the remote
one.";
                        leaf supported value {
                                type boolean;
           default "false"; rt-types:bandwidth-ieee-float32;
                                units Bps;
                                description
             "Indicates whether IS-IS delay metric is supported.";
                                        "Residual bandwidth.";
                        }
         description "IS-IS expense metric container.";
                }
                container error-metric unidirectional-link-available-bandwidth {
                        description
                                "Container for the available bandwidth
                                from the local neighbor to the remote
one.";
                        leaf metric value {
                                type std-metric; rt-types:bandwidth-ieee-float32;
                                units Bps;
                                description
             "This leaf describes the IS-IS error metric value";
                                        "Available bandwidth.";
                        }
         leaf supported
                }
                container unidirectional-link-utilized-bandwidth {
           type boolean;
           default "false";
                        description "IS-IS error metric
                                "Container for IPv4 prefix";
         } the utilized bandwidth
                                from the local neighbor to the remote
one.";
                        leaf value {
                                type rt-types:bandwidth-ieee-float32;
                                units Bps;
                                description "IS-IS error metric container.";
                                        "Utilized bandwidth.";
                        }
                }
        }

        grouping prefix-ipv4-extended neighbor-te-extensions {
                description
                        "Grouping for TE attributes of an IPv4 extended prefix.";
       leaf up-down {
         type boolean;
         description  "Value of up/down bit.";
       }
       leaf ip-prefix {
         type inet:ipv4-address;
         description "IPv4 prefix address";
       } a neighbor as
defined
                        in RFC5305";

                leaf prefix-len admin-group {
                        type uint8; uint32;
                        description "IPv4 prefix length (in bits)";
                                "Administrative group/Resource
Class/Color.";
                }

       leaf metric
                container local-if-ipv4-addrs {
         type wide-metric;
                        description "IS-IS wide metric value";
       } "All local interface IPv4
addresses.";
                        leaf-list tag local-if-ipv4-addr {
                                type uint32; inet:ipv4-address;
                                description
                                        "List of 32-bit tags associated with the local interface IPv4 prefix.";
addresses.";
                        }
                }
                container remote-if-ipv4-addrs {
                        description "All remote interface IPv4
addresses.";
                        leaf-list tag64 remote-if-ipv4-addr {
                                type uint64; inet:ipv4-address;
                                description
                                        "List of 32-bit tags associated with the remote interface IPv4 prefix.";
addresses.";
                        }
       uses prefix-attributes-extension;
                }

     grouping prefix-ipv6-extended {
       description "Grouping for attributes of an IPv6 prefix.";
                leaf up-down te-metric {
                        type boolean; uint32;
                        description "Value of up/down bit."; "TE metric.";
                }
                leaf ip-prefix max-bandwidth {
                        type inet:ipv6-address; rt-types:bandwidth-ieee-float32;
                        description "IPv6 prefix address"; "Maximum bandwidth.";
                }
                leaf prefix-len max-reservable-bandwidth {
                        type uint8; rt-types:bandwidth-ieee-float32;
                        description  "IPv4 prefix length (in bits)"; "Maximum reservable bandwidth.";
                }
                container unreserved-bandwidths {
                        description "All unreserved bandwidths.";
                        list unreserved-bandwidth {
                                leaf metric priority {
                                        type wide-metric; uint8 {
                                                range "0 .. 7";
                                        }
                                        description  "IS-IS wide metric value"; "Priority from 0 to
7.";
                                }
       leaf-list tag
                                leaf unreserved-bandwidth {
                                        type uint32;
rt-types:bandwidth-ieee-float32;
                                        description
           "List of 32-bit tags associated with the IPv4 prefix."; "Unreserved
bandwidth.";
                                }
       leaf-list tag64 {
         type uint64;
                                description
                                        "List of 32-bit tags associated with the IPv4 prefix."; unreserved bandwidths
for different
                                         priorities.";
                        }
                }
       uses prefix-attributes-extension;
        }

  grouping neighbor-extended {
    description
     "Grouping for attributes of an IS-IS extended neighbor.";
    leaf neighbor-id {
      type system-id; extended-system-id;
      description "System-id of the extended neighbor.";
    }
   container instances {
      description "List of all adjacencies between the local
                   system and the neighbor system-id.";
      list instance {
        key id;

        leaf id {
          type uint32;
          description "Unique identifier of an instance of a
                       particular neighbor.";
        }
        leaf metric {
          type wide-metric;
          description "IS-IS wide metric for extended neighbor";
        }
        uses neighbor-gmpls-extensions;
        uses neighbor-te-extensions;
        uses neighbor-extended-te-extensions;
        uses neighbor-link-attributes;
        uses unknown-tlvs;
        description "Instance of a particular adjacency.";
      }
    }
  }

  grouping neighbor {
    description  "IS-IS standard neighbor grouping.";
    leaf neighbor-id neighbor-id {
      type extended-system-id;
      description "IS-IS neighbor system-id";
    }
   container instances {
      description "List of all adjacencies between the local
                   system and the neighbor system-id.";
      list instance {
        key id;
        leaf id {
          type system-id; uint32;
          description "IS-IS neighbor system-id"; "Unique identifier of an instance of a
                       particular neighbor.";
        }
        leaf i-e {
          type boolean;
          description
            "Internal or External (I/E) Metric bit value";
        }
        leaf default-metric {
          type std-metric;
          description "IS-IS default metric value";
        }
        container delay-metric {
          leaf metric {
            type std-metric;
            description "IS-IS delay metric value";
          }
          leaf supported {
            type boolean;
            default "false";
            description "IS-IS delay metric supported";
          }
          description "IS-IS delay metric container";
        }
        container expense-metric {
          leaf metric {
            type std-metric;
            description "IS-IS delay expense metric value";
          }
          leaf supported {
            type boolean;
            default "false";
            description "IS-IS delay expense metric supported";
          }
          description "IS-IS delay expense metric container";
        }
        container error-metric {
          leaf metric {
            type std-metric;
            description "IS-IS error metric value";
          }
          leaf supported {
            type boolean;
            default "false";
            description "IS-IS error metric supported";
          }
          description "IS-IS error metric container";
        }
        description "Instance of a particular adjacency.";
      }
    }
  }

  /* Top level TLVs */

  grouping lsp-entry tlv132-ipv4-addresses {
    leaf-list ipv4-addresses {
      type inet:ipv4-address;
      description "IS-IS LSP database entry groupting";

       leaf decoded-completed
        "List of IPv4 addresses of the IS-IS node - IS-IS
         reference is TLV 132.";
    }
    description "Grouping for TLV132.";
  }
  grouping tlv232-ipv6-addresses {
    leaf-list ipv6-addresses {
      type boolean; inet:ipv6-address;
      description "IS-IS LSP body fully decoded.";
        "List of IPv6 addresses of the IS-IS node - IS-IS
         reference is TLV 232.";
    }
    description "Grouping for TLV232.";
  }
  grouping tlv134-ipv4-te-rid {
    leaf raw-data ipv4-te-routerid {
      type yang:hex-string; inet:ipv4-address;
      description
           "The hexadecial representation
        "IPv4 Traffic Engineering router ID of the complete LSP in
            network-byte order (NBO) as received or originated."; IS-IS node -
         IS-IS reference is TLV 134.";
    }
    description "Grouping for TLV134.";
  }
  grouping tlv140-ipv6-te-rid {
    leaf lsp-id ipv6-te-routerid {
      type lsp-id; inet:ipv6-address;
      description "LSP
        "IPv6 Traffic Engineering router ID of the LSP"; IS-IS node -
         IS-IS reference is TLV 140.";
    }
    description "Grouping for TLV140.";
  }
  grouping tlv129-protocols {
    leaf-list protocol-supported {
      type uint8;
      description
      "List of supported protocols of the IS-IS node -
       IS-IS reference is TLV 129.";
    }
    description "Grouping for TLV129.";
  }
  grouping tlv137-hostname {
    leaf dynamic-hostname {
      type string;
      description
        "Host Name of the IS-IS node - IS-IS reference
         is TLV 137.";
    }
    description "Grouping for TLV137.";
  }
  grouping tlv10-authentication {
    container authentication {
      leaf authentication-type {
        type string;
        description
          "Authentication type to be used with IS-IS node.";
      }
      leaf authentication-key {
        type string;
        description
          "Authentication keyto be used. For security reasons,
           the authentication key MUST NOT be presented in
           plaintext format. It is recommended to use an MD5
           hash to present the authentication-key.";
      }
       leaf checksum {
         type uint16;
      description "LSP checksum";
        "IS-IS node authentication information container -
         IS-IS reference is TLV 10.";
    }
       leaf remaining-lifetime {
         type uint16;
         units "seconds";
    description
           "Remaining lifetime (in seconds) until LSP expiration."; "Grouping for TLV10.";
  }
  grouping tlv229-mt {
    container mt-entries {
      list topology {
        description
          "List of topologies supported";

        leaf sequence mt-id {
          type uint32; uint16 {
            range "0 .. 4095";
          }
          description
           "This leaf describes the sequence number
            "Multi-Topology identifier of the LSP."; topology.";

        }

        leaf attributes {
          type bits {
            bit partitioned {
             description "Originator partition repair supported";
           }
           bit attached-error overload {
              description
                "If set, the originator is attached to
                another area using the referred metric."; overloaded,
                 and must be avoided in path calculation.";
            }
            bit attached-expense attached {
              description
                "If set, the originator is attached to
                another area using the referred metric.";
            }
           bit attached-delay {
          }
          description
               "If set,
            "Attributes of the originator is attached to
                another area using LSP for the referred metric."; associated
             topology.";
        }
      }
      description
        "IS-IS node topology information container -
         IS-IS reference is TLV 229.";
    }
    description "Grouping for TLV229.";
  }

  grouping tlv242-router-capabilities {
    container router-capabilities {
      list router-capability {
          leaf flags {
            type bits {
              bit attached-default flooding {
                position 0;
                description
                  "If the S bit is set, the originator IS-IS Router CAPABILITY
                   TLV MUST be flooded across the entire routing
                   domain. If the S bit is attached to
                another area using clear, the referred metric."; TLV MUST NOT
                   be leaked between levels. This bit MUST NOT
                    be altered during the TLV leaking.";
              }
              bit overload down {
                position 1;
                description
               "If set,
                  "When the originator IS-IS Router CAPABILITY TLV is overloaded,
                and must leaked
                   from level-2 to level-1, the D bit MUST be avoided set.
                   Otherwise, this bit MUST be clear.  IS-IS Router
                   capability TLVs with the D bit set MUST NOT be
                   leaked from level-1 to level-2 in path calculation."; to prevent
                   TLV looping.";
              }
            }
            description "LSP attributes"; "Router Capability Flags";
          }

       leaf-list ipv4-addresses
          container node-tags {
            if-feature node-tag;
            list node-tag {
              leaf tag {
                type inet:ipv4-address; uint32;
                description
           "List of IPv4 addresses of the IS-IS node - IS-IS
            reference is TLV 132."; "Node tag value.";
              }

       leaf-list ipv6-addresses {
         type inet:ipv6-address;
              description "List of IPv6 addresses of the IS-IS tags.";
            }
            description "Container for node - IS-IS
            reference is TLV 232."; admin tags";
          }

          uses unknown-tlvs;

          leaf ipv4-te-routerid binary {
            type inet:ipv4-address; binary;
            description
           "IPv4 Traffic Engineering router ID
              "Binary encoding of the IS-IS node capabilities";
          }
          description
            "IS-IS node capabilities. This list element may
             be extended with detailed information -  IS-IS
             reference is TLV 134."; 242.";
        }
        description "List of router capability TLVs.";
      }
      description "Grouping for TLV242.";
  }

  grouping tlv138-srlg {
    description
      "Grouping for TLV138.";
    container links-srlgs {
      list links {
        leaf ipv6-te-routerid neighbor-id {
          type inet:ipv6-address; extended-system-id;
          description
           "IPv6 Traffic Engineering router ID "System-id of the IS-IS node -
            IS-IS reference is TLV 140."; extended neighbor.";
        }

       leaf-list protocol-supported
        leaf flags {
          type uint8;
          description
         "List of supported protocols of
            "Flags associated with the IS-IS node -
          IS-IS reference is TLV 129."; link.";

        }
        leaf dynamic-hostname link-local-id {
          type string; union {
            type inet:ip-address;
            type uint32;
          }
          description
           "Host Name
            "Local identifier of the IS-IS node - IS-IS reference
            is TLV 137."; link.
            It could be an IPv4 address or a local identifier.";
        }

       container authentication {
        leaf authentication-type link-remote-id {
          type string;
           description
             "Authentication type to be used with IS-IS node.";
         }
         leaf authentication-key union {
            type string; inet:ip-address;
            type uint32;
          }
          description
             "Authentication keyto be used. For security reasons,
            "Remote identifier of the authentication key MUST NOT be presented in
              plaintext format. link.
            It is recommended to use could be an MD5
              hash to present IPv4 address or a remotely learned
            identifier.";
        }
        container srlgs {
          description "List of SRLGs.";
          leaf-list srlg {
            type uint32;
            description
              "SRLG value of the authentication-key."; link.";
          }
        }
        description
           "IS-IS node authentication information container -
            IS-IS reference is TLV 10.";
          "SRLG attribute of a link.";
      }

       container mt-entries {
         list topology {
      description
        "List of topologies supported"; links with SRLGs";
    }
  }

  /* Grouping for LSDB description */

  grouping lsp-entry {
    description "IS-IS LSP database entry groupting";

    leaf MT-ID decoded-completed {
      type uint16 {
               range "0 .. 4095";
             } boolean;
      description
               "Multi-Topolgoy identifier of topology."; "IS-IS LSP body fully decoded.";
    }
    leaf attributes raw-data {
      type bits {
               bit overload { yang:hex-string;
      description
                   "If set,
        "The hexadecial representation of the originator is overloaded,
                    and must be avoided complete LSP in path calculation.";
         network-byte order (NBO) as received or originated.";
    }
               bit attached
    leaf lsp-id {
      type lsp-id;
      description
                   "If set, the originator is attached to
                   another area using the referred metric.";
               }
             }
             description
               "Attributes "LSP ID of the LSP for the associated
                topology.";
           } LSP";
    }
    leaf checksum {
      type uint16;
      description
           "IS-IS node topology information container -
            IS-IS reference is TLV 229."; "LSP checksum";
    }

       list router-capabilities {
    leaf flags remaining-lifetime {
      type bits {
             bit flooding {
               position 0; uint16;
      units "seconds";
      description
                 "If the S bit is set, the IS-IS Router CAPABILITY
                  TLV MUST be flooded across the entire routing
                  domain. If the S bit is clear, the TLV MUST NOT
                  be leaked between levels. This bit MUST NOT
                   be altered during the TLV leaking.";
        "Remaining lifetime (in seconds) until LSP expiration.";
    }
             bit down
    leaf sequence {
               position 1;
      type uint32;
      description
                 "When the IS-IS Router CAPABILITY TLV is leaked
                  from level-2 to level-1, the D bit MUST be set.
                  Otherwise, this bit MUST be clear.  IS-IS Router
                  capability TLVs with
        "This leaf describes the D bit set MUST NOT be
                  leaked from level-1 to level-2 in to prevent
                  TLV looping.";
             }
           }
           description "Router Capability Flags"; sequence number of the LSP.";
    }
         container node-tags {
           if-feature node-tag;
           list node-tag {
    leaf tag attributes {
      type uint32; bits {
        bit partitioned {
          description "Node tag value."; "Originator partition repair supported";
        }
        bit attached-error {
          description "List of tags.";
            "If set, the originator is attached to
             another area using the referred metric.";
        }
        bit attached-expense {
          description "Node Tag container";
            "If set, the originator is attached to
             another area using the referred metric.";
        }

         leaf binary
        bit attached-delay {
           type binary;
          description
             "Binary encoding of
            "If set, the IS-IS node capabilities"; originator is attached to
             another area using the referred metric.";
        }
        bit attached-default {
          description
           "IS-IS node capabilities container. This container may
            be extended with detailed information -  IS-IS
            reference
            "If set, the originator is TLV 242."; attached to
             another area using the referred metric.";
        }
        bit overload {
          description
            "If set, the originator is overloaded,
             and must be avoided in path calculation.";
        }
      }
      description "LSP attributes";
    }

    uses tlv132-ipv4-addresses;
    uses tlv232-ipv6-addresses;
    uses tlv134-ipv4-te-rid;
    uses tlv140-ipv6-te-rid;
    uses tlv129-protocols;
    uses tlv137-hostname;
    uses tlv10-authentication;
    uses tlv229-mt;
    uses tlv242-router-capabilities;
    uses tlv138-srlg;
    uses unknown-tlvs;

    container is-neighbor {
      list neighbor {
        key neighbor-id;

        uses neighbor;
        description "List of neighbors.";
      }
      description
        "Standard IS neighbors container - IS-IS reference is
         TLV 2.";
    }

    container extended-is-neighbor {
      list neighbor {
        key neighbor-id;

        uses neighbor-extended;
        description
          "List of extended IS neighbors";
      }
      description
        "Standard IS extended neighbors container - IS-IS
         reference is TLV 22";
    }

    container ipv4-internal-reachability {
      list prefixes {
        uses prefix-ipv4-std;
        description "List of prefixes.";
      }
      description
      "IPv4 internal reachability information container - IS-IS
       reference is TLV 128.";
    }

    container ipv4-external-reachability {
      list prefixes {
        uses prefix-ipv4-std;
        description "List of prefixes.";
      }
      description
        "IPv4 external reachability information container -
         IS-IS reference is TLV 130.";
    }

    container extended-ipv4-reachability {
      list prefixes {
        uses prefix-ipv4-extended;
        uses unknown-tlvs;
        description "List of prefixes.";
      }
      description
        "IPv4 extended reachability information container -
         IS-IS reference is TLV 135.";
    }

    container mt-is-neighbor {
      list neighbor {
        leaf mt-id {
          type uint16 {
            range "0 .. 4095";
          }
          description "Multi-topology (MT) identifier";
        }
        uses neighbor-extended;
        description "List of neighbors.";
      }
      description
        "IS-IS multi-topology neighbor container - IS-IS
         reference is TLV 223.";
    }

    container mt-extended-ipv4-reachability {
      list prefixes {
        leaf mt-id {
          type uint16 {
            range "0 .. 4095";
          }
          description  "Multi-topology (MT) identifier";
        }
        uses prefix-ipv4-extended;
        uses unknown-tlvs;
        description "List of extended prefixes.";
      }
      description
        "IPv4 multi-topolgy (MT) extended reachability
         information container - IS-IS reference is TLV 235.";
    }

    container mt-ipv6-reachability {
      list prefixes {
        leaf MT-ID {
          type uint16 {
            range "0 .. 4095";
          }
          description "Multi-topology (MT) identifier";
        }
        uses prefix-ipv6-extended;
        uses unknown-tlvs;
        description "List of IPv6 extended prefixes.";
      }
      description
        "IPv6 multi-topolgy (MT) extended reachability
         information container - IS-IS reference is TLV 237.";
    }

    container ipv6-reachability {
      list prefixes {
        uses prefix-ipv6-extended;
        uses unknown-tlvs;
        description "List of IPv6 prefixes.";
      }
      description
        "IPv6 reachability information container - IS-IS
         reference is TLV 236.";
    }
  }

  grouping lsdb {
    description "Link State Database (LSDB) grouping";
    container database {
      config false;
      list level-db {
        key level;
        leaf level {
          type level-number;
          description "LSDB level number (1 or 2)";
        }
        list lsp {
          key lsp-id;
          uses lsp-entry;
          description "List of LSPs in LSDB";
        }
        description "LSP list for LSDB level container";
      }
      description "IS-IS Link State database container";
    }
  }

  /* Augmentations */

  augment "/rt:routing/"
    +"rt:ribs/rt:rib/rt:routes/rt:route" {
    when "rt:source-protocol = 'isis:isis'" {
      description "IS-IS-specific route attributes.";
    }
    uses route-content;
    description
      "This augments route object in RIB with IS-IS-specific
       attributes.";
  }

  augment "/if:interfaces/if:interface" {
    leaf clns-mtu {
      type uint16;
      description "CLNS MTU of the interface";
    }
    description "ISO specific interface config."; parameters.";
  }

  augment "/rt:routing/rt:control-plane-protocols/"
    +"rt:control-plane-protocol" {
    when "rt:type = 'isis:isis'" {
      description
        "This augment is only valid when routing protocol
         instance type is 'isis'";
    }
    description
      "This augments a routing protocol instance with IS-IS
       specific parameters.";
    container isis {
      must "count(area-address) > 0" {
        error-message
          "At least one area-address must be configured.";
        description
          "Enforce configuration of at least one area.";
      }

      uses isis-global-cfg;
         container fast-reroute {
           if-feature fast-reroute;
           uses fast-reroute-global-cfg;
           uses fast-reroute-global-state;
           description
             "IP Fast ReRoute (IPFRR) global container";
         }
         container spf-control {
           leaf paths {
             if-feature max-ecmp;
             type uint16 {
               range "1..32";
             }
             description
               "Maximum number of Equal-Cost Multi-Path (ECMP) paths.";
           }
           container ietf-spf-delay {
             if-feature ietf-spf-delay;
             uses ietf-spf-delay-cfg; instance-config;
      uses ietf-spf-delay-state;
             description "IETF SPF delay algorithm container";
           }
           description
             "SPF computation-related information container";
         } instance-state;

      container topologies {
        if-feature multi-topology;
        list topology {
          key "name";
          leaf enable {
            type boolean;
            description "Topology enable configuration";
          }
          leaf name {
            type leafref {
              path "../../../../../../rt:ribs/rt:rib/rt:name";
            }
            description
              "Routing Information Base (RIB) corresponding
               to topology.";
          }

          uses isis-global-topologies-cfg; multi-topology-config;

          description "List of topologies";
        }
        description "Multi-topology container";
      }
      container interfaces {
        list interface {
          key "name";
          leaf name {
            type if:interface-ref;

            description
              "Reference to the interface within
               the routing-instance.";
          }
          uses isis-if-cfg;
             container fast-reroute {
               if-feature fast-reroute;
               uses fast-reroute-if-cfg;
               description
                 "IP Fast ReRoute (IPFRR) interface container";
             } interface-config;
          container topologies {
            if-feature multi-topology;
            list topology {
              key name;

              leaf name {
                type leafref {
                  path "../../../../../../../../"+
                    "rt:ribs/rt:rib/rt:name";
                }

                description
                  "Routing Information Base (RIB) corresponding
                   to topology.";
              }
              uses isis-if-topologies-cfg; multi-topology-interface-config;
              description "List of interface topologies";
            }
            description "Multi-topology container";
          }
             uses adjacency-state;
             uses event-counters;
             uses packet-counters;
          description "List of IS-IS interfaces.";
           }
           description
             "IS-IS interface specific configuration container";
         }
         uses spf-log;
         uses lsp-log;
         uses hostname-db;
         uses lsdb;
         uses local-rib;
         uses system-counters; interfaces.";
        }
        description
          "IS-IS interface specific configuration container";
      }

      description
        "IS-IS configuration/state top-level container";
    }
  }

  /* RPC methods */

  rpc clear-adjacency {
    description
      "This RPC request clears a particular set of IS-IS
       adjacencies. If the operation fails due to an internal
       reason, then the error-tag and error-app-tag should be
       set indicating the reason for the failure.";
    input {

      leaf routing-protocol-instance-name {
        type instance-state-ref; leafref {
          path "/rt:routing/rt:control-plane-protocols/"
             + "rt:control-plane-protocol/rt:name";
        }
        mandatory "true";
        description
          "Name of the IS-IS protocol instance whose IS-IS
           information is being queried.

           If the corresponding IS-IS instance doesn't exist,
           then the operation will fail with an error-tag of
           'data-missing' and an error-app-tag of
           'routing-protocol-instance-not-found'.";
      }
      leaf level {
        type level;
        description
          "IS-IS level of the adjacency to be cleared. If the
           IS-IS level is level-1-2, both level 1 and level 2
           adjacencies would be cleared.

           If the value provided is different from the one
           authorized in the enum type, then the operation
           SHALL fail with an error-tag of 'data-missing' and
           an error-app-tag of 'bad-isis-level'.";
      }
      leaf interface {
        type string; if:interface-ref;
        description
          "IS-IS interface name.

           If the corresponding IS-IS interface doesn't exist,
           then the operation SHALL fail with an error-tag of
           'data-missing' and an error-app-tag of
           'isis-interface-not-found'.";
      }
    }
  }

  rpc clear-database {
    description
      "This RPC request clears a particular  IS-IS database. If
       the operation fails for an IS-IS internal reason, then
       the error-tag and error-app-tag should be set
       indicating the reason for the failure.";
    input {
      leaf routing-protocol-instance-name {
        type instance-state-ref; leafref {
          path "/rt:routing/rt:control-plane-protocols/"
             + "rt:control-plane-protocol/rt:name";
        }
        mandatory "true";
        description
          "Name of the IS-IS protocol instance whose IS-IS
           database(s) is/are being cleard. cleared.

           If the corresponding IS-IS instance doesn't exist,
           then the operation will fail with an error-tag of
           'data-missing' and an error-app-tag of
           'routing-protocol-instance-not-found'.";
      }
      leaf level {
        type level;
        description
          "IS-IS level of the adjacency to be cleared. If the
           IS-IS level is level-1-2, both level 1 and level 2
           databases would be cleared.

           If the value provided is different from the one
           authorized in the enum type, then the operation
           SHALL fail with an error-tag of 'data-missing' and
           an error-app-tag of 'bad-isis-level'.";
      }
    }
  }

  /* Notifications */

  notification database-overload {
    uses notification-instance-hdr;

    leaf overload {
      type enumeration {
        enum off {
          description
            "Indicates IS-IS instance has left overload state";
        }
        enum on {
          description
            "Indicates IS-IS instance has entered overload state";
        }

      }
      description "New overload state of the IS-IS instance";
    }
    description
      "This notification is sent when an IS-IS instance
       overload state changes.";
  }

  notification lsp-too-large {
    uses notification-instance-hdr;
    uses notification-interface-hdr;

    leaf pdu-size {
      type uint32;
      description "Size of the LSP PDU";
    }
    leaf lsp-id {
      type lsp-id;
      description "LSP ID";
    }
    description
      "This notification is sent when we attempt to propagate
       an LSP that is larger than the dataLinkBlockSize for the
       circuit.  The notification generation must be throttled
       with at least 5 seconds betweeen successive
       notifications.";
  }

  notification if-state-change {
    uses notification-instance-hdr;
    uses notification-interface-hdr;

    leaf state {
      type if-state-type;
      description "Interface state.";
    }
    description
      "This notification is sent when an interface
       state change is detected.";
  }

  notification corrupted-lsp-detected {
    uses notification-instance-hdr;
    leaf lsp-id {
      type lsp-id;
      description "LSP ID";
    }
    description
      "This notification is sent when we find that
       an LSP that was stored in memory has become
       corrupted.";
  }

  notification attempt-to-exceed-max-sequence {
    uses notification-instance-hdr;
    leaf lsp-id {
      type lsp-id;
      description "LSP ID";
    }
    description
      "This notification is sent when the system
       wraps the 32-bit sequence counter of an LSP.";
  }

  notification id-len-mismatch {
    uses notification-instance-hdr;
    uses notification-interface-hdr;

    leaf pdu-field-len {
      type uint8;
      description "Size of the ID length in the received PDU";
    }
    leaf raw-pdu {
      type binary;
      description "Received raw PDU.";
    }
    description
      "This notification is sent when we receive a PDU
       with a different value for the System ID length.
       The notification generation must be throttled
       with at least 5 seconds betweeen successive
       notifications.";
  }

  notification max-area-addresses-mismatch {
    uses notification-instance-hdr;
    uses notification-interface-hdr;

    leaf max-area-addresses {
      type uint8;
      description "Received number of supported areas";
    }
    leaf raw-pdu {
      type binary;
      description "Received raw PDU.";
    }
    description
      "This notification is sent when we receive a PDU
       with a different value for the Maximum Area Addresses.
       The notification generation must be throttled
       with at least 5 seconds betweeen successive
       notifications.";
  }

  notification own-lsp-purge {
    uses notification-instance-hdr;
    uses notification-interface-hdr;
    leaf lsp-id {
      type lsp-id;
      description "LSP ID";
    }
    description
      "This notification is sent when the system receives
       a PDU with its own system ID and zero age.";
  }

  notification sequence-number-skipped {
    uses notification-instance-hdr;
    uses notification-interface-hdr;
    leaf lsp-id {
      type lsp-id;
      description "LSP ID";
    }
    description
      "This notification is sent when the system receives a
       PDU with its own system ID and different contents. The
       system has to reoriginate the LSP with a higher sequence
       number.";
  }

  notification authentication-type-failure {
    uses notification-instance-hdr;
    uses notification-interface-hdr;
    leaf raw-pdu {
      type binary;
      description "Received raw PDU.";
    }
    description
      "This notification is sent when the system receives a
       PDU with the wrong authentication type field.
       The notification generation must be throttled
       with at least 5 seconds betweeen successive
       notifications.";
  }

  notification authentication-failure {
    uses notification-instance-hdr;
    uses notification-interface-hdr;
    leaf raw-pdu {
      type binary;
      description "Received raw PDU.";
    }
    description
      "This notification is sent when the system receives
       a PDU with the wrong authentication information.
       The notification generation must be throttled with
       with at least 5 seconds betweeen successive
       notifications.";
  }

  notification version-skew {
    uses notification-instance-hdr;
    uses notification-interface-hdr;
    leaf protocol-version {
      type uint8;
      description "Protocol version received in the PDU.";
    }
    leaf raw-pdu {
      type binary;
      description "Received raw PDU.";
    }
    description
      "This notification is sent when the system receives a
       PDU with a different protocol version number.
       The notification generation must be throttled
       with at least 5 seconds betweeen successive
       notifications.";
  }

  notification area-mismatch {
    uses notification-instance-hdr;
    uses notification-interface-hdr;
    leaf raw-pdu {
      type binary;
      description "Received raw PDU.";
    }
    description
      "This notification is sent when the system receives a
       Hello PDU from an IS that does not share any area
       address. The notification generation must be throttled
       with at least 5 seconds betweeen successive
       notifications.";
  }

  notification rejected-adjacency {
    uses notification-instance-hdr;
    uses notification-interface-hdr;
    leaf raw-pdu {
      type binary;
      description
        "Received raw PDU.";

    }
    leaf reason {
      type string;
      description
        "The system may provide a reason to reject the
         adjacency. If the reason is not available,
         an empty string will be returned.";
    }
    description
      "This notification is sent when the system receives a
       Hello PDU from an IS but does not establish an adjacency
       for some reason. The notification generation must be
       throttled with at least 5 seconds betweeen successive
       notifications.";
  }

  notification protocols-supported-mismatch {
    uses notification-instance-hdr;
    uses notification-interface-hdr;
    leaf raw-pdu {
      type binary;
      description "Received raw PDU.";
    }
    leaf-list protocols {
      type uint8;
      description
        "List of protocols supported by the remote system.";
    }
    description
      "This notification is sent when the system receives a
       non-pseudonode LSP that has no matching protocols
       supported. The notification generation must be throttled
       with at least 5 seconds betweeen successive
       notifications.";
  }

  notification lsp-error-detected {
    uses notification-instance-hdr;
    uses notification-interface-hdr;
    leaf lsp-id {
      type lsp-id;
      description "LSP ID.";
    }
    leaf raw-pdu {
      type binary;
      description "Received raw PDU.";
    }
    leaf error-offset {
      type uint32;
      description
        "If the problem is a malformed TLV, the error-offset
         points to the start of the TLV. If the problem is with
         the LSP header, the error-offset points to the errant
         byte";
    }
    leaf tlv-type {
      type uint8;
      description
        "If the problem is a malformed TLV, the tlv-type is set
         to the type value of the suspicious TLV. Otherwise,
         this leaf is not present.";
    }
    description
      "This notification is sent when the system  receives an
   '
       LSP with a parse error. The notification generation must
       be throttled with at least 5 seconds betweeen successive
       notifications.";
  }

  notification adjacency-state-change {
    uses notification-instance-hdr;
    uses notification-interface-hdr;
    leaf neighbor {
      type string;
      description
        "Name of the neighbor. If the name of the neighbor is
         not available, it is not returned.";
    }
    leaf neighbor-system-id {
      type system-id;
      description "Neighbor system-id";
    }
    leaf state {
      type adj-state-type;

      description "New state of the IS-IS adjacency.";
    }
    leaf reason {
      type string;
      description
        "If the adjacency is going to DOWN,  this leaf provides
         a reason for the adjacency going down. The reason is
         provided as a text. If the adjacency is going to UP, no
         reason is provided.";
    }
    description
      "This notification is sent when an IS-IS adjacency
       moves to Up state or to Down state.";
  }

  notification lsp-received {
    uses notification-instance-hdr;
    uses notification-interface-hdr;

    leaf lsp-id {
      type lsp-id;
      description "LSP ID";
    }
    leaf sequence {
      type uint32;
      description "Sequence number of the received LSP.";
    }
    leaf received-timestamp {
      type yang:timestamp;

      description "Timestamp when the LSP was received.";
    }
    leaf neighbor-system-id {
      type system-id;
      description "Neighbor system-id of LSP sender";
    }
    description
      "This notification is sent when an LSP is received.
       The notification generation must be throttled with at
       least 5 seconds betweeen successive notifications.";
   }

  notification lsp-generation {
    uses notification-instance-hdr;

    leaf lsp-id {
      type lsp-id;
      description "LSP ID";
    }
    leaf sequence {
      type uint32;
      description "Sequence number of the received LSP.";
    }
    leaf send-timestamp {
      type yang:timestamp;

      description "Timestamp when our LSP was regenerated.";
    }
    description
      "This notification is sent when an LSP is regenerated.
       The notification generation must be throttled with at
       least 5 seconds betweeen successive notifications.";
  }
}

<CODE ENDS>

7.  Security Considerations

   Configuration and state data defined

   The YANG module specified in this document are defines a schema for data
   that is designed to be accessed via the network management protocols such
   as NETCONF protocol [RFC6241].

   As IS-IS [RFC6241] or RESTCONF [RFC8040].  The lowest NETCONF layer
   is an IGP protocol (critical piece of the network), ensuring
   stability secure transport layer, and security of the protocol mandatory-to-implement secure
   transport is mandatory for Secure Shell (SSH) [RFC6242].  The lowest RESTCONF layer
   is HTTPS, and the network
   service.

   Authors recommends to implement NETCONF access control model
   ([RFC6536]) mandatory-to-implement secure transport is TLS
   [RFC8446]

   The Network Configuration Access Control Model (NACM) [RFC8341]
   provides the means to restrict access for particular NETCONF or
   RESTCONF users to a preconfigured subset of all available NETCONF or part of the configuration to
   specific users.  Access control to RPCs is also critical as RPC
   allows to clear
   RESTCONF protocol datastructures that would definitively
   impact the network service.  This kind operations and content.

   There are a number of RPC needs only to be used data nodes defined in specific cases by well-known experienced users.

   Authors consider this YANG module that all the configuration are
   writable/creatable/deletable (i.e., config true, which is the
   default).  These data nodes may be considered as
   sensitive/vulnerable as well as RPCs.  But security teams can decide
   to open sensitive or vulnerable
   in some part of the configuration network environments.  Write operations (e.g., edit-config)
   to less experienced users
   depending these data nodes without proper protection can have a negative
   effect on network operations.  For IS-IS, the internal organization, for example:

   o  User FullWrite: would access ability to modify IS-IS
   configuration will allow the whole data model.  This kind
      of profile may be restricted entire IS-IS domain to few experienced people.

   o  User PartialWrite: would only access be compromised
   including creating adjacencies with unauthorized routers to misroute
   traffic, isolate routers, or mount a massive Denial-of-Service (DoS)
   attack.  A user should consider all the configuration part within
      /isis/interfaces/interface.  So this kind nodes are
   sensible.

   Some of profile the readable data nodes in this YANG module may be considered
   sensitive or vulnerable in some network environments.  It is restricted
      to creation/modification/deletion of interfaces.  This profile
      does not have access to RPC.

   o  User Read: would only access thus
   important to the operational states.

   Unauthorized control read access to configuration (e.g., via get, get-config, or RPC may cause high damages
   notification) to
   the network service. these data nodes.  The "isis/database" may contain authentication information.  As
   presented in the description exposure of the "/isis/database/level-
   1/lsp/authentication/authentication-key", Link State
   Database (LSDB) will expose the detailed topology of the network
   including authentication parameters.  Implementations MUST
   never be displayed NOT
   provide a configured authentication key in a plaintext clear text format for security reason.
   Authors recommend in
   response to any request (e.g., via get, get-config).

   For IS-IS authentication, configuration is supported vua the usage
   specification of MD5 to display key-chain [RFC8177] or return the
   authentication-key.

   Some authentication-key may also be required direction specification
   of key and authentication algorithm.  Hence, authentification
   configuration using the "auth-table-trailer" case in the "isis" writable
   container.  When configuring IS-IS using
   "authentication" container inherits the NETCONF protocol,
   authors recommends security considerations of
   [RFC8177].  This includes the usage considerations with respect to the
   local storage and handling of secure transport authentication keys.

   Some of NETCONF using SSH
   ([RFC6242]). the RPC operations in this YANG module may be considered
   sensitive or vulnerable in some network environments.  It is thus
   important to control access to these operations.  The OSPF YANG
   module support the "clear-adjacency" and "clear-database" RPCs.  If
   access too either of these is compromised, they can result in
   temporary network outages be employed to mount DoS attacks.

8.  Contributors

   Authors would like to thank Kiran Agrahara Sreenivasa, Dean
   Bogdanovic, Yingzhen Qu, Yi Yang for their major contributions to the
   draft.

9.  Acknowledgements

   TBD.

10.  IANA Considerations

   The IANA is requested to assign two new URIs from the IETF XML
   registry ([RFC3688]).  Authors are suggesting the following URI:

           URI: urn:ietf:params:xml:ns:yang:ietf-isis
           Registrant Contact: IS-IS WG
           XML: N/A, the requested URI is an XML namespace

   This document also requests one new YANG module name in the YANG
   Module Names registry ([RFC6020]) with the following suggestion:

           name: ietf-isis
           namespace: urn:ietf:params:xml:ns:yang:ietf-isis
           prefix: isis
           reference: RFC XXXX

11.  Change log for ietf-isis YANG module

11.1.  From version -24 to version -25

   o  RPC clear-adjacency uses now an interface reference instead of a
      string.

   o  Use expanded "address-family" rather than "af" in the model.

   o  Fix pattern for area-address.

   o  Removed unnecessary identities.

   o  Added an instances container and list in the modeling of neighbors
      in the LSDB.  This is to manage the case where there are parallel
      links between two neighbors.

   o  Notification instance header: removed routing-instance leaf
      (alignment with OSPF).

   o  Notification instance header: changed routing-protocol-name to a
      reference.

   o  Notification interface header: changed interface to a reference.

   o  RPCs: changed instance-state-ref typedef to a leafref.  Removed
      associated typedef.

   o  Revised some groupings and their names (alignment with OSPF).

   o  Some description alignment with OSPF.

   o  auto-cost container alignment with OSPF.

   o  MT-ID leaf in database description renamed (lower-case) mt-id.

   o  In lsp-log grouping, leaf change is renamed reason to align with
      OSPF.

   o  Added some link attributes (GMPLS, TE, extended TE, SRLGs) in the
      LSDB.

   o  Added extended-system-id typedef which contains the systemid plus
      the pseudonode number.

   o  Add support of POI Purge Originator Identification.

11.2.  From version -22 to version -24

   o  Fix revision date of the module

11.2. module.

11.3.  From version -21 to version -22

   o  TE router-id modeling alignment with OSPF.

   o  Add max-ecmp + feature in spf-control container (alignment with
      OSPF).

11.3.

11.4.  From version -20 to version -21

   o  Model revision date fix

11.4.

11.5.  From version -19 to version -20

   o  Moved to Yang 1.1

   o  Lower case enumerations

   o  Add RFC references to features

   o  Remove segment-routing feature

   o  Modified BFD activation modeling

11.5.

11.6.  From version -18 to version -19

   o  Align with draft-ietf-netmod-rfc8022bis.

   o  Modify address family types as per draft-ietf-rtgwg-routing-types-
      17.

11.6.

11.7.  From version -17 to version -18

   o  NMDA compliancy.

   o  Set some default values.

   o  Align with iana-rt-types module.

11.7.

11.8.  From version -16 to version -17

   o  Cosmetic fixes.

   o  Use of rt-types model.

11.8.

11.9.  From version -15 to version -16

   o  Alignment with last IETF key chain model.

   o  lsp-log "change" leaf moved as an identity.

   o  Incremental SPF removed from spf-log types.

11.9.

11.10.  From version -14 to version -15

   o  Alignment with OSPF model done:

      *  Added spf-control container with IETF SPF delay algorithm as a
         feature.

      *  Added graceful-restart options.

      *  Added nsr as a feature.

      *  Removed per topology FRR.  Need to be augmented if necessary.

      *  Created an ldp container within mpls.

      *  Renamed igp-ldp-sync to igp-sync.

      *  Added auto-cost container.

      *  Moved reference-bandwidth under auto-cost container.

      *  Added IS-IS local RIB as operational state.

      *  Added decode-completed and raw-data leaves in the LSDB model.

      *  Modified the notification header.

11.10.

11.11.  From version -13 to version -14

   o  Segment Routing extensions are now in a separate document.

11.11.

11.12.  From version -12 to version -13

   o  Move feature nlpid-control to container rather than list.

   o  Rename multi-topology to topologies to align with OSPF.

   o  Rename bfd/enabled to bfd/enable for consistency reason.

   o  Add support for NSR with a feature.

11.12.

11.13.  From version -09 to version -12

   o  Rename node-tag container to node-tags.

11.13.

11.14.  From version -08 to version -09

   o  Added container before af list.

   o  Added container before topology list.

   o  Aligned LFA if per level cfg.

   o  Align to draft-ietf-netmod-routing-cfg-23.

11.14.

11.15.  From version -07 to version -08

   o  Remove selector from system-id type.

   o  Add some default values.

   o  Moved lists to containers+groupings for per level configuration.

   o  remove routing-instance as per core routing model v21.

   o  added BFD leaf (no more BFD protocol model).

   o  changed keychain module reference.

11.15.

11.16.  From version -05 to version -07

   o  Move Overload config from list to container.

   o  Move Overload-max-metric config from list to container.

   o  Move preference config from list to container.

   o  Add Node flag in config.

   o  Removed BFD config => moved to isis-bfd module.

   o  Remove call to routing policy model.

11.16.

11.17.  From version -03 to version -05

   o  Correct invalid references to previous versions of core routing
      model.

   o  Remove BFD config and replace by groupings from ietf-bfd.

   o  Adding routing-policy support through routing-policy model.

11.17.

11.18.  From version -02 to version -03

   o  Reviewed config and op state groupings.

   o  Add default value to lfa candidate-disabled.

   o  Add enable leaf to isis container to reflect admin state.

   o  Move to VRF centric only.

   o  Segment routing is part os a separate module.

11.18.

11.19.  From version -01 to version -02

   o  Adding IPFRR.

   o  Adding igp-ldp-sync.

   o  Adding segment-routing.

   o  Adding instance reference to operational states.

   o  Move AF type from string to identity.

   o  Updated router-capability in LSDB description.

   o  packet counters moved to interface-packet-counters.

   o  Added modification information in lsp-log.

   o  Removing igp-ldp-sync timer in IS-IS.

   o  Defining hierarchy for operational states.

   o  Adding clns-mtu.

   o  Adding key-chain.

11.19.

11.20.  From version -00 to version -01

   o  Interface metric move from af container to interface container.

   o  Hello-padding on interface moved to hello-padding-disable with
      empty type.

   o  three-way-handshake removed.

   o  route preference changed to a choice.

   o  csnp-authentication/psnp-authentication merged to authentication
      container.

   o  lsp-gen-interval-exp-delay removed.

   o  Added overload-max-metric feature.

   o  overload-max-metric is in a separate container.

   o  Change hello-padding to container.

   o  Change bfd to container.

   o  Make BFD a feature.

   o  Create mpls-te container and put router-id inside.

   o  Remove GR helper disable and timers.

12.  References

12.1.  Normative References

   [I-D.ietf-netmod-routing-cfg]
              Lhotka, L.

   [I-D.ietf-bfd-yang]
              Rahman, R., Zheng, L., Jethanandani, M., Networks, J., and A. Lindem, "A YANG
              G. Mirsky, "YANG Data Model for Routing
              Management", draft-ietf-netmod-routing-cfg-25 (work in
              progress), November 2016.

   [I-D.ietf-rtgwg-yang-key-chain]
              Lindem, A., Qu, Y., Yeung, D., Chen, I., and Z. Zhang,
              "Routing Key Chain YANG Data Model", draft-ietf-rtgwg-
              yang-key-chain-24 Bidirectional Forwarding
              Detection (BFD)", draft-ietf-bfd-yang-17 (work in
              progress), April 2017. August 2018.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              DOI 10.17487/RFC3688, January 2004,
              <https://www.rfc-editor.org/info/rfc3688>.

   [RFC5120]  Przygienda, T., Shen, N., and N. Sheth, "M-ISIS: Multi
              Topology (MT) Routing in Intermediate System to
              Intermediate Systems (IS-ISs)", RFC 5120,
              DOI 10.17487/RFC5120, February 2008,
              <https://www.rfc-editor.org/info/rfc5120>.

   [RFC5286]  Atlas, A., Ed. and A. Zinin, Ed., "Basic Specification for
              IP Fast Reroute: Loop-Free Alternates", RFC 5286,
              DOI 10.17487/RFC5286, September 2008,
              <https://www.rfc-editor.org/info/rfc5286>.

   [RFC5443]  Jork, M., Atlas, A., and L. Fang, "LDP IGP
              Synchronization", RFC 5443, DOI 10.17487/RFC5443, March
              2009, <https://www.rfc-editor.org/info/rfc5443>.

   [RFC6020]  Bjorklund, M., Ed., "YANG - A Data Modeling Language for
              the Network Configuration Protocol (NETCONF)", RFC 6020,
              DOI 10.17487/RFC6020, October 2010,
              <https://www.rfc-editor.org/info/rfc6020>.

   [RFC6241]  Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
              and A. Bierman, Ed., "Network Configuration Protocol
              (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
              <https://www.rfc-editor.org/info/rfc6241>.

   [RFC6242]  Wasserman, M., "Using the NETCONF Protocol over Secure
              Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
              <https://www.rfc-editor.org/info/rfc6242>.

   [RFC6536]  Bierman, A. and M. Bjorklund, "Network Configuration
              Protocol (NETCONF) Access Control Model",

   [RFC6991]  Schoenwaelder, J., Ed., "Common YANG Data Types",
              RFC 6536, 6991, DOI 10.17487/RFC6536, March 2012,
              <https://www.rfc-editor.org/info/rfc6536>. 10.17487/RFC6991, July 2013,
              <https://www.rfc-editor.org/info/rfc6991>.

   [RFC7490]  Bryant, S., Filsfils, C., Previdi, S., Shand, M., and N.
              So, "Remote Loop-Free Alternate (LFA) Fast Reroute (FRR)",
              RFC 7490, DOI 10.17487/RFC7490, April 2015,
              <https://www.rfc-editor.org/info/rfc7490>.

   [RFC7950]  Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
              RFC 7950, DOI 10.17487/RFC7950, August 2016,
              <https://www.rfc-editor.org/info/rfc7950>.

   [RFC8040]  Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
              Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
              <https://www.rfc-editor.org/info/rfc8040>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

   [RFC8177]  Lindem, A., Ed., Qu, Y., Yeung, D., Chen, I., and J.
              Zhang, "YANG Data Model for Key Chains", RFC 8177,
              DOI 10.17487/RFC8177, June 2017,
              <https://www.rfc-editor.org/info/rfc8177>.

   [RFC8294]  Liu, X., Qu, Y., Lindem, A., Hopps, C., and L. Berger,
              "Common YANG Data Types for the Routing Area", RFC 8294,
              DOI 10.17487/RFC8294, December 2017,
              <https://www.rfc-editor.org/info/rfc8294>.

   [RFC8341]  Bierman, A. and M. Bjorklund, "Network Configuration
              Access Control Model", STD 91, RFC 8341,
              DOI 10.17487/RFC8341, March 2018,
              <https://www.rfc-editor.org/info/rfc8341>.

   [RFC8342]  Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
              and R. Wilton, "Network Management Datastore Architecture
              (NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
              <https://www.rfc-editor.org/info/rfc8342>.

   [RFC8343]  Bjorklund, M., "A YANG Data Model for Interface
              Management", RFC 8343, DOI 10.17487/RFC8343, March 2018,
              <https://www.rfc-editor.org/info/rfc8343>.

   [RFC8349]  Lhotka, L., Lindem, A., and Y. Qu, "A YANG Data Model for
              Routing Management (NMDA Version)", RFC 8349,
              DOI 10.17487/RFC8349, March 2018,
              <https://www.rfc-editor.org/info/rfc8349>.

   [RFC8446]  Rescorla, E., "The Transport Layer Security (TLS) Protocol
              Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
              <https://www.rfc-editor.org/info/rfc8446>.

12.2.  Informative References

   [RFC8340]  Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
              BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
              <https://www.rfc-editor.org/info/rfc8340>.

Appendix A.  Example of IS-IS configuration in XML

   This section gives an example of configuration of an IS-IS instance
   on a device.  The example is written in XML.

   <?xml version="1.0" encoding="utf-8"?>
   <data xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
     <routing xmlns="urn:ietf:params:xml:ns:yang:ietf-routing">
         <name>SLI</name>
         <router-id>1.1.1.1</router-id>
      <description/>
      <interfaces>
        <interface>
          <name>Loopback0</name>
        </interface>
                <interface>
          <name>Eth1</name>
        </interface>
      </interfaces>
         <control-plane-protocols>
           <control-plane-protocol>
          <name>ISIS</name>
             <name>ISIS-example</name>
             <description/>
          <type>isis:isis</type>
             <type>
               <type xmlns:isis="urn:ietf:params:xml:ns:yang:ietf-isis">
               isis:isis
               </type>
             </type>
             <isis xmlns="urn:ietf:params:xml:ns:yang:ietf-isis">
                 <enable>true</enable>
                 <level-type>level-2</level-type>
                 <system-id>87FC.FCDF.4432</system-id>
                 <area-address>49.0001</area-address>
              <mpls-te>
                <ipv4-router-id>1.1.1.1</ipv4-router-id>
              </mpls-te>
                 <mpls>
                   <te-rid>
                     <ipv4-router-id>192.0.2.1</ipv4-router-id>
                   </te-rid>
                 </mpls>
                 <lsp-lifetime>65535</lsp-lifetime>
                 <lsp-refresh>65000</lsp-refresh>
                 <metric-type>
                <value>wide</value>
                   <value>wide-only</value>
                 </metric-type>
                 <default-metric>
                   <value>111111</value>
                 </default-metric>
              <afs>
                                <af>
                                        <af>ipv4-unicast</af>
                                        <enabled>true</enabled>
                                </af>
              </afs>
                 <address-families>
                   <address-family-list>
                     <address-family>ipv4</address-family>
                     <enable>true</enable>
                   </address-family-list>
                   <address-family-list>
                     <address-family>ipv6</address-family>
                     <enable>true</enable>
                   </address-family-list>
                 </address-families>
                 <interfaces>
                   <interface>
                     <name>Loopback0</name>
                     <tag>200</tag>
                     <metric>
                       <value>0</value>
                     </metric>
                     <passive>true</passive>
                   </interface>
                   <interface>
                     <name>Eth1</name>
                     <level-type>level-2</level-type>
                     <interface-type>point-to-point</interface-type>
                     <metric>
                       <value>167890</value>
                     </metric>
                   </interface>
                 </interfaces>
             </isis>
           </control-plane-protocol>

         </control-plane-protocols>
     </routing>
     <interfaces xmlns="urn:ietf:params:xml:ns:yang:ietf-interfaces">
       <interface>
         <name>Loopback0</name>
         <description/>
      <type/>
      <link-up-down-trap-enable/>
         <type xmlns:ianaift="urn:ietf:params:xml:ns:yang:iana-if-type">
         ianaift:softwareLoopback
         </type>
         <link-up-down-trap-enable>enabled</link-up-down-trap-enable>
         <ipv4 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip">
        <mtu/>
           <address>
          <ip>1.1.1.1</ip>
             <ip>192.0.2.1</ip>
             <prefix-length>32</prefix-length>
           </address>
         </ipv4>
         <ipv6 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip">
           <address>
             <ip>2001:DB8::1</ip>
             <prefix-length>128</prefix-length>
           </address>
         </ipv6>
       </interface>
       <interface>
         <name>Eth1</name>
         <description/>
      <type/>
      <link-up-down-trap-enable/>
         <type xmlns:ianaift="urn:ietf:params:xml:ns:yang:iana-if-type">
         ianaift:ethernetCsmacd
         </type>
         <link-up-down-trap-enable>enabled</link-up-down-trap-enable>
         <ipv4 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip">
        <mtu/>
           <address>
          <ip>10.0.0.1</ip>
             <ip>198.51.100.1</ip>
             <prefix-length>30</prefix-length>
           </address>
         </ipv4>
         <ipv6 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip">
           <address>
             <ip>2001:DB8:0:0:FF::1</ip>
             <prefix-length>64</prefix-length>
           </address>
         </ipv6>
       </interface>
     </interfaces>
   </data>

Authors' Addresses

   Stephane Litkowski
   Orange

   Email: stephane.litkowski@orange.com

   Derek Yeung
   Arrcus, Inc

   Email: derek@arrcus.com

   Acee Lindem
   Cisco Systems

   Email: acee@cisco.com

   Jeffrey Zhang
   Juniper Networks

   Email: zzhang@juniper.net

   Ladislav Lhotka
   CZ.NIC

   Email: lhotka@nic.cz