CCAMP Working Group                                   E. Bellagamba, Ed.
Internet-Draft                                         L. Andersson, Ed.
Intended status: Standards Track                                Ericsson
Expires: April 14, June 15, 2013                                P. Skoldstrom, Ed.
                                                                Acreo AB
                                                                 D. Ward
                                                                 Juniper
                                                                   Cisco
                                                               A. Takacs
                                                                Ericsson
                                                        October 11,
                                                       December 12, 2012

Configuration of Pro-Active  Operations, Administration, and Maintenance
    (OAM) Functions for MPLS-based Transport Networks using RSVP-TE
              draft-ietf-ccamp-rsvp-te-mpls-tp-oam-ext-10
              draft-ietf-ccamp-rsvp-te-mpls-tp-oam-ext-11

Abstract

   This specification describes the configuration of pro-active MPLS-TP
   Operations, Administration, and Maintenance (OAM) Functions for a
   given LSP using a set of TLVs that are carried by the RSVP-TE
   protocol.

   This document is a product of a joint Internet Engineering Task Force
   (IETF) / International Telecommunication Union Telecommunication
   Standardization Sector (ITU-T) effort to include an MPLS Transport
   Profile within the IETF MPLS and PWE3 architectures to support the
   capabilities and functionalities of a packet transport network.

Status of this Memo

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   provisions of BCP 78 and BCP 79.

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   This Internet-Draft will expire on April 14, June 15, 2013.

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   document authors.  All rights reserved.

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Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.1.  Contributing Authors . . . . . . . . . . . . . . . . . . .  4
     1.2.  Requirements Language  . . . . . . . . . . . . . . . . . .  4
   2.  Overview of MPLS OAM for Transport Applications  . . . . . . .  4
   3.  Theory of Operations . . . . . . . . . . . . . . . . . . . . .  5
     3.1.  MPLS  MPLS-TP OAM Configuration Operation Overview . . . . . . . .  5
       3.1.1.  Configuration of BFD sessions  . . . . . . . . . . . .  5
       3.1.2.  Configuration of Performance Monitoring  . . . . . . .  6
       3.1.3.  Configuration of Fault Management Signals  . . . . . .  7
     3.2.  OAM Configuration TLV  . . . . . . . . . . . . . . . . . .  7
     3.3.  BFD Configuration sub-TLV  . . . . . . . . . . . . . . . .  9  8
       3.3.1.  Local Discriminator  BFD Identifiers sub-TLV  . . . . . . . . . . . . . 11 . . 10
       3.3.2.  Negotiation Timer Parameters sub-TLV . . . . . . . . . 11
       3.3.3.  BFD Authentication sub-TLV . . . . . . . . . . . . . . 13 12
     3.4.  Performance Monitoring sub-TLV . . . . . . . . . . . . . . 13
       3.4.1.  MPLS OAM PM Loss sub-TLV . . . . . . . . . . . . . . . 14
       3.4.2.  MPLS OAM PM Delay sub-TLV  . . . . . . . . . . . . . . 16 15
     3.5.  MPLS OAM FMS sub-TLV . . . . . . . . . . . . . . . . . . . 17 16
   4.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 18 17
   5.  BFD OAM configuration errors . . . . . . . . . . . . . . . . . 18
   6.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 19 18
   7.  Security Considerations  . . . . . . . . . . . . . . . . . . . 19 18
   8.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 19
     8.1.  Normative References . . . . . . . . . . . . . . . . . . . 19
     8.2.  Informative References . . . . . . . . . . . . . . . . . . 20
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 21

1.  Introduction

   This document describes the configuration of pro-active MPLS-TP
   Operations, Administration, and Maintenance (OAM) Functions for a
   given LSP using TLVs carried by RSVP-TE [RFC3209]. [RFC3473].  In particular it
   specifies the mechanisms necessary to establish MPLS-TP OAM entities
   at the maintenance points for monitoring and performing measurements
   on an LSP, as well as defining information elements and procedures to
   configure pro-active MPLS MPLS-TP OAM functions running between LERs.
   Initialization and control of on-demand MPLS MPLS-TP OAM functions are
   expected to be carried out by directly accessing network nodes via a
   management interface; hence configuration and control of on-demand
   OAM functions are out-of-scope for this document.

   The Transport Profile of MPLS must, by definition [RFC5654], be
   capable of operating without a control plane.  Therefore there are
   several options for configuring MPLS-TP OAM, without a control plane
   by either using an NMS or LSP Ping, or with a control plane using
   signaling protocols RSVP-TE and/or T-LDP.  Use of T-LDP for
   configuration of MPLS-TP OAM is outside of scope of this document. such as RSVP-TE.

   Pro-active MPLS MPLS-TP OAM is performed by three four different protocols,
   Bidirectional Bi-
   directional Forwarding Detection (BFD) [RFC6428] for Continuity
   Check/Connectivity Verification, the delay measurement protocol (DM)
   [RFC6374] for delay and delay variation (jitter) measurements, and
   the loss measurement protocol (LM) [RFC6374] for packet loss and
   throughput measurements.  Additionally there is a number of Fault
   Management Signals that can be configured.

   BFD is a protocol that provides low-overhead, fast detection of
   failures in the path between two forwarding engines, including the
   interfaces, data link(s), and to the extent possible the forwarding
   engines themselves.  BFD can be used to track the liveliness and
   detect data plane failures of MPLS-TP point-to-point and might also
   be extended to support point-to-multipoint connections.

   The delay and loss measurements protocols [RFC6374] use a simple
   query/response model for performing bidirectional measurements that
   allows the originating node to measure packet loss and delay in both
   directions.  By timestamping and/or writing current packet counters
   to the measurement packets at four times (Tx and Rx in both
   directions) current delays and packet losses can be calculated.  By
   performing successive delay measurements the delay variation (jitter)
   can be calculated.  Current throughput can be calculated from the
   packet loss measurements by dividing the number of packets sent/
   received with the time it took to perform the measurement, given by
   the timestamp in LM header.  Combined with a packet generator the
   throughput measurement can be used to measure the maximum capacity of
   a particular LSP.  It should be noted that here we are not
   configuring on-demand throughput estimates based on saturating the
   connection as defined in [RFC6371].  Rather, we only enable the
   estimation of the current throughput based on loss measurements.

   MPLS Transport Profile (MPLS-TP) describes a profile of MPLS that
   enables operational models typical in transport networks, while
   providing additional OAM, survivability and other maintenance
   functions not currently supported by MPLS.  [RFC5860] defines the
   requirements for the OAM functionality of MPLS-TP.

   This document is a product of a joint Internet Engineering Task Force
   (IETF) / International Telecommunication Union Telecommunication
   Standardization Sector (ITU-T) effort to include an MPLS Transport
   Profile within the IETF MPLS and PWE3 architectures to support the
   capabilities and functionalities of a packet transport network.

1.1.  Contributing Authors

   This document is the result of a large team of authors and
   contributors.  The following is a list of the co-authors:

      Gregory Mirsky

      John Drake

      Benoit Tremblay

1.2.  Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].

2.  Overview of MPLS OAM for Transport Applications

   [MPLS-TP-OAM-FWK]

   [RFC6371] describes how MPLS MPLS-TP OAM mechanisms are operated to meet
   transport requirements outlined in [RFC5860].

   [BFD-CCCV]

   [RFC6428] specifies two BFD operation modes: 1) "CC mode", which uses
   periodic BFD message exchanges with symmetric timer settings,
   supporting Continuity Check, 2) "CV/CC mode" which sends unique
   maintenance entity identifiers in the periodic BFD messages
   supporting Connectivity Verification as well as Continuity Check.

   [RFC6374] specifies mechanisms for performance monitoring of LSPs, in
   particular it specifies loss and delay measurement OAM functions.

   [MPLS-FMS]

   [RFC6427] specifies fault management signals with which a server LSP
   can notify client LSPs about various fault conditions to suppress
   alarms or to be used as triggers for actions in the client LSPs.  The
   following signals are defined: Alarm Indication Signal (AIS), Link
   Down Indication (LDI) and Locked Lock Report (LKR).  To indicate client
   faults associated with the attachment circuits Client Signal Failure
   Indication (CSF) can be used.  CSF is described in [MPLS-TP-OAM-FWK]
   and in the context of this document is for further study.

   [MPLS-TP-OAM-FWK]

   [RFC6371] describes the mapping of fault conditions to consequent
   actions.  Some of these mappings may be configured by the operator,
   depending on the application of the LSP.  The following defects are
   identified: Loss Of Continuity (LOC), Misconnectivity, MEP
   Misconfiguration and Period Misconfiguration.  Out of these defect
   conditions, the following consequent actions may be configurable: 1)
   whether or not the LOC defect should result in blocking the outgoing
   data traffic; 2) whether or not the "Period Misconfiguration defect"
   should result in a signal fail condition.

3.  Theory of Operations

3.1.  MPLS  MPLS-TP OAM Configuration Operation Overview

   RSVP-TE, or alternatively LSP Ping [LSP-PING CONF], [LSP-PING-CONF], can be used to
   simply enable the different OAM functions, by setting the
   corresponding flags in the "OAM Functions TLV".  For a more detailed
   configuration one may include sub-TLVs for the different OAM
   functions in order to specify various parameters in detail.

   Typically intermediate nodes should not process or modify any of the
   OAM configuration TLVs but simply forward them to the end-node.
   There is one exception to this and that is if the "MPLS OAM FMS sub-
   TLV" is present.  This sub-TLV has to be examined even by
   intermediate nodes.  The sub-TLV MAY be present if a flag is set in
   the "Function Flags sub-TLV", see section [3.2.  OAM Configuration
   TLV].

3.1.1.  Configuration of BFD sessions

   For this specification, BFD MUST be run in either one of the two
   modes:

      - Asynchronous mode, where both sides should be in active mode

      - Unidirectional mode

   In the simplest scenario LSP Ping, RSVP-TE, or alternatively RSVP-TE [RSVP-TE
   CONF], LSP Ping [LSP-
   PING-CONF], is used only to bootstrap a BFD session for an LSP,
   without any timer negotiation.

   Timer negotiation can be performed either in subsequent BFD control
   messages (in this case the operation is similar to LSP Ping based
   bootstrapping described in [RFC5884]) or directly in the LSP ping
   configuration RSVP-TE
   signaling messages.

   When BFD Control packets are transported in the G-ACh they are not
   protected by any end-to-end checksum, only lower-layers are providing
   error detection/correction.  A single bit error, e.g. a flipped bit
   in the BFD State field could cause the receiving end to wrongly
   conclude that the link is down and in turn trigger protection
   switching.  To prevent this from happening the "BFD Configuration
   sub-TLV" has an Integrity flag that when set enables BFD
   Authentication using Keyed SHA1 with an empty key (all 0s) [RFC5880].
   This would make every BFD Control packet carry an SHA1 hash of itself
   that can be used to detect errors.

   If BFD Authentication using a pre-shared key / password is desired
   (i.e. authentication and not only error detection) the "BFD
   Authentication sub-TLV" MUST be included in the "BFD Configuration
   sub-TLV".  The "BFD Authentication sub-TLV" is used to specify which
   authentication method that should be used and which pre-shared key /
   password that should be used for this particular session.  How the
   key exchange is performed is out of scope of this document.

3.1.2.  Configuration of Performance Monitoring

   It is possible to configure Performance Monitoring functionalities
   such as Loss, Delay, Delay variation (jitter), and Throughput as
   described in [RFC6374].

   When configuring Performance monitoring functionalities it is
   possible to choose either the default configuration, by only setting
   the respective flags in the "OAM functions TLV", or a customized
   configuration.  To customize the configuration one would set the
   respective flags in the including the respective Loss and/or Delay
   sub-TLVs).

   By setting the PM Loss flag in the "OAM Functions TLV" and including
   the "MPLS OAM PM Loss sub-TLV" one can configure the measurement
   interval and loss threshold values for triggering protection.

   Delay measurements are configured by setting PM Delay flag in the
   "OAM Functions TLV" and including the "MPLS OAM PM Loss sub-TLV" one
   can configure the measurement interval and the delay threshold values
   for triggering protection.

3.1.3.  Configuration of Fault Management Signals

   To configure Fault Monitoring Signals and their refresh time the FMS
   flag in the "OAM Functions TLV" MUST be set and the "MPLS OAM FMS
   sub-TLV" included.  When configuring Fault Monitoring Signals it can
   be chosen either the default configuration (by only setting the
   respective flags in the "OAM functions TLV") or a customized
   configuration (by including the "MPLS OAM FMS sub-TLV").

   If an intermediate point is meant to originate fault management
   signal messages this means that such an intermediate point is
   associated to a server MEP through a co-located MPLS-TP client/server
   adaptation function.  Such a server MEP needs to be configured by its
   own RSVP-TE session (or, alternatively, via an NMS or LSP-ping).
   However, by setting the "Fault Management subscription" flag in the
   "MPLS OAM FMS sub-TLV" a client LSP can indicate that it would like
   an association to be created to the server MEP(s) on any intermediate
   nodes.

3.2.  OAM Configuration TLV

   The "OAM Configuration TLV" is depicted TLV", defined in the following figure.  It [OAM-CONF-FWK], specifies the
   OAM functions that are to be used for the LSP and it is
   defined in [OAM-CONF-FWK].  The "OAM Configuration TLV" LSP.  This TLV is carried in the
   LSP_ATTRIBUTES object in Path and Resv messages.

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |           Type (2) (IANA)     |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    OAM Type   |                Reserved                       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                           sub-TLVs                            ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type: indicates

   This document extends the "OAM Configuration TLV" (2) (IANA to assign).

   OAM Type: one octet that specifies the technology specific OAM Type.
   If the requested OAM Type is not supported, an error must be
   generated: "OAM Problem/Unsupported OAM Type".

   This document defines by defining a new
   OAM Type: "MPLS OAM" (suggested value 2, IANA to assign) from the
   "RSVP-TE OAM Configuration Registry".  The "MPLS OAM" type is set to
   request the establishment of OAM functions for MPLS-TP LSPs.  The
   specific OAM functions are specified in the "Function Flags" sub-TLV
   as depicted in [OAM-CONF-FWK].

   The receiving edge LSR when the MPLS-TP OAM Type is requested should
   check which OAM Function Flags are set in the "Function Flags TLV"
   (also defined in [OAM-CONF-FWK]) and look for the corresponding
   technology specific configuration TLVs.

   Additional corresponding sub-TLVs are as follows:

      - "BFD Configuration sub-TLV", which MUST be included if the CC
      and/or the CV OAM Function flag is set.  This sub-TLV MUST carry a
      "BFD Local Discriminator sub-TLV" and a "Timer Negotiation
      Parameters sub-TLV" if the N flag is cleared.  If the I flag is
      set, the "BFD Authentication sub-TLV" may be included.

      - "MPLS OAM PM Loss sub-TLV" within the "Performance Monitoring
      sub-TLV", which MAY be included if the PM/Loss OAM Function flag
      is set.  If the "MPLS OAM PM Loss sub-TLV" is not included,
      default configuration values are used.  Such sub-TLV MAY also be
      included in case the Throughput function flag is set and there is
      the need to specify measurement interval different from the
      default ones.  In fact the throughput measurement make use of the
      same tool as the loss measurement, hence the same TLV is used.

      - "MPLS OAM PM Delay sub-TLV" within the "Performance Monitoring
      sub-TLV", which MAY be included if the PM/Delay OAM Function flag
      is set.  If the "MPLS OAM PM Delay sub-TLV" is not included,
      default configuration values are used.

      - "MPLS OAM FMS sub-TLV", which MAY be included if the FMS OAM
      Function flag is set.  If the "MPLS OAM FMS sub-TLV" is not
      included, default configuration values are used.

   Moreover, if the CV or CC flag Flag is set, the CC flag MUST be set as well.
   The format of an MPLS-TP CV/CC message is shown in [BFD-CCCV] [RFC6428] and it
   requires, together with the BFD control Control packet information, the "Unique MEP-ID of source of BFD packet".  [MPLS-TP-IDENTIF]
   defines the composition of such identifier as:

   <"Unique MEP-ID of source of BFD packet"> ::=
   <src_node_id><src_tunnel_num><lsp_num>

   Note that support "LSP
   MEP-ID".  The "LSP MEP-ID" contain four identifiers:

      - MPLS-TP Global_ID

      - MPLS-TP Node Identifier

      - Tunnel_Num

      - LSP_Num

   These values need to be correctly set by both ingress and egress when
   transmitting a CV packet and both ingress and egress needs to know
   what to expect when receving a CV packet.  Most of ITU IDs is out-of-scope.

   GMPLS signaling [RFC3473] these values can
   be derived from the Path and Resv messages [RFC3473], which uses a
   5-tuple to uniquely identify an LSP within an operator's network.
   This tuple is composed of a Tunnel Sender Address, Tunnel Endpoint
   Address, Tunnel_ID, Extended Tunnel ID, and Tunnel Sender
   Address and (GMPLS) LSP_ID.

   Hence,

   However, not all the following mapping is used without values can be derived from the need of redefining a
   new TLV for MPLS-TP proactive CV purpose.

      - standard RSVP-TE
   objects, in particular the locally assigned Tunnel ID = src_tunnel_num

      - Tunnel Sender Address = src_node_id

      - at the egress
   cannot be derived by the ingress node.  Therefor the full LSP ID = LSP_Num

   "Tunnel ID" and "Tunnel Sender Address" are included MEP-ID
   used by the ingress has to be carried in the "SESSION"
   object [RFC3209], which is mandatory "BFD Identifiers sub-
   TLV" in both the Path message and Resv messages.

   "LSP ID" will be the same on both directions and it is included egress LSP MEP-ID in the "SENDER_TEMPLATE" object [RFC3209] which is mandatory same way in Path
   messages.

   [Author's note:
   the same "Unique MEP-ID of source" will be likely
   required for Performance monitoring purposes.  This need to be agreed
   with [RFC6374] authors.] Resv message.

3.3.  BFD Configuration sub-TLV

   The "BFD Configuration sub-TLV" (depicted below) is defined for BFD
   OAM specific configuration parameters.  The "BFD Configuration sub-
   TLV" is carried as a sub-TLV of the "OAM Configuration TLV".

   This TLV accommodates generic BFD OAM information and carries sub-
   TLVs.

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  BFD Conf. Type (3) (IANA)    |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Vers.| PHB |N|S|I|G|U|B|    Reserved (set to all 0s)           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                           sub-TLVs                            ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type: indicates a new type, the "BFD Configuration sub-TLV" (IANA to
   define).
   define, suggested value 3).

   Length: indicates the total length including sub-TLVs.

   Version: identifies the BFD protocol version.  If a node does not
   support a specific BFD version an error must be generated: "OAM
   Problem/Unsupported OAM Version".

   PHB: Identifies the Per-Hop Behavior (PHB) to be used for periodic
   continuity monitoring messages.

   BFD Negotiation (N): If set timer negotiation/re-negotiation via BFD
   Control Messages is enabled, when cleared it is disabled.

   Symmetric session (S): If set the BFD session MUST use symmetric
   timing values.

   Integrity (I): If set BFD Authentication MUST be enabled.  If the
   "BFD Configuration sub-TLV" does not include a "BFD Authentication
   sub-TLV" the authentication MUST use Keyed SHA1 with an empty pre-
   shared key (all 0s).

   Encapsulation Capability (G): if set, it shows the capability of
   encapsulating BFD messages into G-Ach channel.  If both the G bit and
   U bit are set, configuration gives precedence to the G bit.

   Encapsulation Capability (U): if set, it shows the capability of
   encapsulating BFD messages into UDP packets.  If both the G bit and U
   bit are set, configuration gives precedence to the G bit.

   Bidirectional (B): if set, it configures BFD in the Bidirectional
   mode.  If it is not set it configures BFD in unidirectional mode.  In
   the second case, the source node does not expect any Discriminator
   values back from the destination node.

   Reserved: Reserved for future specification and set to 0 on
   transmission and ignored when received.

   The "BFD Configuration sub-TLV" MUST include the following sub-TLVs
   in the Path message:

      - "Local Discriminator "BFD Identifiers sub-TLV";

      - "Negotiation Timer Parameters sub-TLV" if the N flag is cleared.

   The "BFD Configuration sub-TLV" MUST include the following sub-TLVs
   in the Resv message:

      - "Local Discriminator "BFD Identifiers sub-TLV;"

      - "Negotiation Timer Parameters sub-TLV" if:

         - the N and S flags are cleared, or if:

         - the N flag is cleared and the S flag is set, and the
         Negotiation Timer Parameters sub-TLV received by the egress
         contains unsupported values.  In this case an updated
         Negotiation Timer Parameters sub-TLV, containing values
         supported by the egress node, is returned to the ingress.

3.3.1.  Local Discriminator  BFD Identifiers sub-TLV

   The "Local Discriminator "BFD Identifiers sub-TLV" is carried as a sub-TLV of the "BFD
   Configuration sub-TLV" and is depicted below.

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Lcl. Discr. BFD ident.  Type (1) (IANA)   |            Length             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Local Discriminator                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       MPLS-TP Global_ID                       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                    MPLS-TP Node Identifier                    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |           Tunnel_Num          |            LSP_Num            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   Type: indicates a new type, the Local Discriminator sub-TLV "BFD Identifiers sub-TLV" (1) (IANA
   to define).

   Length: indicates the TLV total length in octets. (8)

   Local Discriminator: A unique, nonzero discriminator value generated
   by the transmitting system and referring to itself, used to
   demultiplex multiple BFD sessions between the same pair of systems.

   MPLS-TP Global_ID, Node Identifier, Tunnel_Num, and LSP_Num: all set
   as defined in [RFC6370].

3.3.2.  Negotiation Timer Parameters sub-TLV

   The "Negotiation Timer Parameters sub-TLV" is carried as a sub-TLV of
   the "BFD Configuration sub-TLV" and is depicted below.

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Nego. Timer Neg. Type (2) (IANA)   |             Length            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |         Acceptable Min. Asynchronous TX interval              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |         Acceptable Min. Asynchronous RX interval              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |               Required Echo TX Interval                       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type: indicates a new type, the "Negotiation Timer Parameters sub-
   TLV" (IANA to define). define, suggested value 2).

   Length: indicates the TLV total length in octets. (16)

   Acceptable Min. Asynchronous TX interval: in case of S (symmetric)
   flag set in the "BFD Configuration sub-TLV", it expresses the desired
   time interval (in microseconds) at which the ingress LER intends to
   both transmit and receive BFD periodic control packets.  If the
   receiving edge LSR can not support such value, it can SHOULD reply with
   an interval greater than the one proposed.

   In case of S (symmetric) flag cleared in the "BFD Configuration sub-
   TLV", this field expresses the desired time interval (in
   microseconds) at which a edge LSR intends to transmit BFD periodic
   control packets in its transmitting direction.

   Acceptable Min. Asynchronous RX interval: in case of S (symmetric)
   flag set in the "BFD Configuration sub-TLV", this field MUST be equal
   to "Acceptable Min. Asynchronous TX interval" and has no additional
   meaning respect to the one described for "Acceptable Min.
   Asynchronous TX interval".

   In case of S (symmetric) flag cleared in the "BFD Configuration sub-
   TLV", it expresses the minimum time interval (in microseconds) at
   which edge LSRs can receive BFD periodic control packets.  In case
   this value is greater than the "Acceptable Min. Asynchronous TX
   interval" received from the other edge LSR, such edge LSR MUST adopt
   the interval expressed in this "Acceptable Min. Asynchronous RX
   interval".

   Required Echo TX Interval: the minimum interval (in microseconds)
   between received BFD Echo packets that this system is capable of
   supporting, less any jitter applied by the sender as described in
   [RFC5880] sect. 6.8.9.  This value is also an indication for the
   receiving system of the minimum interval between transmitted BFD Echo
   packets.  If this value is zero, the transmitting system does not
   support the receipt of BFD Echo packets.  If the receiving system can
   not support this value an error MUST be generated "Unsupported BFD TX
   rate interval".

3.3.3.  BFD Authentication sub-TLV

   The "BFD Authentication sub-TLV" is carried as a sub-TLV of the "BFD
   Configuration sub-TLV" and is depicted below.

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    BFD Auth. Type (3) (IANA)  |            Length             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Auth Type   |  Auth Key ID  |         Reserved (0s)         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type: indicates a new type, the "BFD Authentication sub-TLV" (IANA to
   define).

   Length: indicates the TLV total length in octets. (8)

   Auth Type: indicates which type of authentication to use.  The same
   values as are defined in section 4.1 of [RFC5880] are used.

   Auth Key ID: indicates which authentication key or password
   (depending on Auth Type) should be used.  How the key exchange is
   performed is out of scope of this document.

   Reserved: Reserved for future specification and set to 0 on
   transmission and ignored when received.

3.4.  Performance Monitoring sub-TLV

   If the "OAM functions TLV" has either the L (Loss), D (Delay) or T
   (Throughput) flag set, the "Performance Monitoring sub-TLV" MUST be
   present.

   The "Performance Monitoring sub-TLV" provides the configuration
   information mentioned in Section 7 of [RFC6374].  It includes support
   for the configuration of quality thresholds and, as described in
   [RFC6374], "the crossing of which will trigger warnings or alarms,
   and result reporting and exception notification will be integrated
   into the system-wide network management and reporting framework."

   In case the values need to be different than the default ones the
   "Performance Monitoring sub-TLV", "MPLS OAM PM Loss sub-TLV" MAY
   include the following sub-TLVs:

      - "MPLS OAM PM Loss sub-TLV" if the L flag is set in the "OAM
      functions TLV";

      - "MPLS OAM PM Delay sub-TLV" if the D flag is set in the "OAM
      functions TLV";

   The "Performance Monitoring sub-TLV" depicted below is carried as a
   sub-TLV of the "OAM Functions TLV".

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Perf Monitoring Type(4) (IANA)|          Length               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |D|L|J|Y|K|C|            Reserved (set to all 0s)               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                           sub-TLVs                            ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Length:

   Type: indicates a new type, the TLV total length in "Performance Monitoring sub-TLV"
   (IANA to define, suggested value 4).

   Length: indicates the TLV total length in octets.

   Configuration Flags, for the specific function description please
   refer to [RFC6374]:

      - D: Delay inferred/direct (0=INFERRED, 1=DIRECT)

      - L: Loss inferred/direct (0=INFERRED, 1=DIRECT)

      - J: Delay variation/jitter (1=ACTIVE, 0=NOT ACTIVE)

      - Y: Dyadic (1=ACTIVE, 0=NOT ACTIVE)

      - K: Loopback (1=ACTIVE, 0=NOT ACTIVE)

      - C: Combined (1=ACTIVE, 0=NOT ACTIVE)

   Reserved: Reserved for future specification and set to 0 on
   transmission and ignored when received.

3.4.1.  MPLS OAM PM Loss sub-TLV

   The "MPLS OAM PM Loss sub-TLV" depicted below is carried as a sub-TLV
   of the "Performance Monitoring sub-TLV".

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  PM Loss Type (1) (IANA)      |          Length               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | OTF |T|B|              Reserved (set to all 0s)               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                    Measurement Interval                       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Test Interval                           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                      Loss Threshold                           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type: indicates a new type, the "MPLS OAM PM Loss sub-TLV" (IANA to
   define, suggested value 1).

   Length: indicates the length of the parameters in octets (20).

   OTF: Origin Timestamp Format of the Origin Timestamp field described
   in [RFC6374].  By default it is set to IEEE 1588 version 1.

   Configuration Flags, please refer to [RFC6374] for further details:

      - T: Traffic-class-specific measurement indicator.  Set to 1 when
      the measurement operation is scoped to packets of a particular
      traffic class (DSCP value), and 0 otherwise.  When set to 1, the
      DS field of the message indicates the measured traffic class.  By
      default it is set to 1.

      - B: Octet (byte) count.  When set to 1, indicates that the
      Counter 1-4 fields represent octet counts.  When set to 0,
      indicates that the Counter 1-4 fields represent packet counts.  By
      default it is set to 0.

   Reserved: Reserved for future specification and set to 0 on
   transmission and ignored when received.

   Measurement Interval: the time interval (in milliseconds) at which
   Loss Measurement query messages MUST be sent on both directions.  If
   the edge LSR receiving the Path message can not support such value,
   it can SHOULD reply back with a higher interval.  By default it is set to
   (100) as per [RFC6375].

   Test Interval: test messages interval in milliseconds as described in
   [RFC6374].  By default it is set to (10) as per [RFC6375].

   Loss Threshold: the threshold value of measured lost packets per
   measurement over which
   protections MUST action(s) SHOULD be triggered.  By default it is set to (200).

3.4.2.  MPLS OAM PM Delay sub-TLV

   The "MPLS OAM PM Delay sub-TLV" depicted below is carried as a sub-
   TLV of the "OAM Functions TLV". "Performance Monitoring sub-TLV".

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  PM Delay Type (2) (IANA)     |          Length               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | OTF |T|B|             Reserved (set to all 0s)                |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                    Measurement Interval                       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Test Interval                           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                      Delay Threshold                          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type: indicates a new type, the "MPLS OAM PM Loss sub-TLV" (IANA to
   define, suggested value 1). 2).

   Length: indicates the length of the parameters in octets (20).

   OTF: Origin Timestamp Format of the Origin Timestamp field described
   in [RFC6374].  By default it is set to IEEE 1588 version 1.

   Configuration Flags, please refer to [RFC6374] for further details:

      - T: Traffic-class-specific measurement indicator.  Set to 1 when
      the measurement operation is scoped to packets of a particular
      traffic class (DSCP value), and 0 otherwise.  When set to 1, the
      DS field of the message indicates the measured traffic class.  By
      default it is set to 1.

      - B: Octet (byte) count.  When set to 1, indicates that the
      Counter 1-4 fields represent octet counts.  When set to 0,
      indicates that the Counter 1-4 fields represent packet counts.  By
      default it is set to 0.

   Reserved: Reserved for future specification and set to 0 on
   transmission and ignored when received.

   Measurement Interval: the time interval (in milliseconds) at which
   Delay Measurement query messages MUST be sent on both directions.  If
   the edge LSR receiving the Path message can not support such value,
   it can reply back with a higher interval.  By default it is set to
   (1) (1000)
   as per [RFC6375].

   Test Interval: test messages interval (in milliseconds) as described
   in [RFC6374].  By default it is set to (10) as per [RFC6375].

   Delay Threshold: the threshold value of measured two-way delay (in
   milliseconds) over which protections MUST action(s) SHOULD be triggered.  By default
   it is set to (2).

3.5.  MPLS OAM FMS sub-TLV

   The "MPLS OAM FMS sub-TLV" depicted below is carried as a sub-TLV of
   the "OAM Configuration sub-TLV".  When both working and protection
   paths are signaled, both LSPs SHOULD be signaled with identical
   settings of the E flag, T flag, and the refresh timer.

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  MPLS OAM FMS Type (5) (IANA) |            Length             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |E|S|T| Reserved (set to all 0s)|      Refresh Timer      | PHB |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   Type: indicates a new type, the "MPLS OAM FMS sub-TLV" (IANA to
   define).

   Length: indicates the TLV total length in octets. (8)

   FMS Signal Flags are used to enable the FMS signals at end point MEPs
   and the Server MEPs of the links over which the LSP is forwarded.  In
   this document only the S flag pertains to Server MEPs.

   The following flags are defined:

      - E: Enable Alarm Indication Signal (AIS) and Locked Lock Report (LKR)
      signalling as described in [MPLS-FMS]. [RFC6427].  Default value is 1
      (enabled).

      - S: Indicate to a server MEP that its should transmit AIS and LKR
      signals on the client LSP.  Default value is 0 (disabled).

      - T: Set timer value, enabled the configuration of a specific
      timer value.  Default value is 0 (disabled).

      - Remaining bits: Reserved for future specification and set to 0.

   Refresh Timer: indicates the refresh timer of fault indication
   messages, in seconds.  The range is value MUST be between 1 to 20 seconds. seconds as
   specified for the Refresh Timer field in [RFC6427].  If the edge LSR
   receiving the Path message can not support the value it can SHOULD reply
   back
   with a higher interval.

   - timer value.

   PHB: identifies the per-hop behavior of packets with fault management
   information.

4.  IANA Considerations

   This document specifies the following new TLV types:

      - "BFD Configuration" type: 3;

      - "Performance Monitoring" type: 4;

      - "MPLS OAM FMS" type: 5.

   sub-TLV types to be carried in the "BFD Configuration sub-TLV":

      - "Local Discriminator" "BFD Identifiers" sub-TLV type: 1;
      - "Negotiation Timer Parameters" sub-TLV type: 2.

      - "BFD Authentication" sub-TLV type: 3.

   sub-TLV types to be carried in the "BFD Configuration "Performance monitoring sub-TLV":

      - "MPLS OAM PM Loss" type: 1;

      - "MPLS OAM PM Delay" type: 2;

5.  BFD OAM configuration errors

   In addition to error values specified in [OAM-CONF-FWK] and [ETH-OAM]
   this document defines the following values for the "OAM Problem"
   Error Code:

      - "MPLS OAM Unsupported Functionality";

      - "OAM Problem/Unsupported TX rate interval";

      - "OAM Problem/Unsupported RX rate interval";

      - "OAM Problem/Unsupported unsupported Authentication Type";

      - "OAM Problem, mismatch of Authentication Key ID ".

6.  Acknowledgements

   The authors would like to thank David Allan, Lou Berger, Annamaria
   Fulignoli, Eric Gray, Andras Kern, David Jocha and David Sinicrope
   for their useful comments.

7.  Security Considerations

   The signaling of OAM related parameters and the automatic
   establishment of OAM entities introduces additional security
   considerations to those discussed in [RFC3473].  In particular, a
   network element could be overloaded if an attacker were to request
   high frequency liveliness monitoring of a large number of LSPs,
   targeting a single network element.

   Security aspects will be covered in more detailed in subsequent
   versions of this document.

8.  References
8.1.  Normative References

   [MPLS-FMS]
              Swallow, G., Fulignoli, A., Vigoureux, M., Boutros, S.,
              and D. Ward, "MPLS Fault Management OAM", 2009,
              <draft-ietf-mpls-tp-fault>.

   [MPLS-TP-IDENTIF]
              Bocci, M., Swallow, G., and E. Gray, "MPLS-TP
              Identifiers", 2010, <draft-ietf-mpls-tp-identifiers>.

   [OAM-CONF-FWK]
              Takacs, A., Fedyk, D., and J. van He, "OAM Configuration
              Framework for GMPLS RSVP-TE", 2009,
              <draft-ietf-ccamp-oam-configuration-fwk>.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC3209]  Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
              and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
              Tunnels", RFC 3209, December 2001.

   [RFC3471]  Berger, L., "Generalized Multi-Protocol Label Switching
              (GMPLS) Signaling Functional Description", RFC 3471,
              January 2003.

   [RFC3473]  Berger, L., "Generalized Multi-Protocol Label Switching
              (GMPLS) Signaling Resource ReserVation Protocol-Traffic
              Engineering (RSVP-TE) Extensions", RFC 3473, January 2003.

   [RFC5586]  Bocci, M., Vigoureux, M., and S. Bryant, "MPLS Generic
              Associated Channel", RFC 5586, June 2009.

   [RFC5654]  Niven-Jenkins, B., Brungard, D., Betts, M., Sprecher, N.,
              and S. Ueno, "Requirements of an MPLS Transport Profile",
              RFC 5654, September 2009.

   [RFC5860]  Vigoureux, M., Ward, D., and M. Betts, "Requirements for
              Operations, Administration, and Maintenance (OAM) in MPLS
              Transport Networks", RFC 5860, May 2010.

   [RFC5880]  Katz, D. and D. Ward, "Bidirectional Forwarding Detection
              (BFD)", RFC 5880, June 2010.

   [RFC5884]  Aggarwal, R., Kompella, K., Nadeau, T., and G. Swallow,
              "Bidirectional Forwarding Detection (BFD) for MPLS Label
              Switched Paths (LSPs)", RFC 5884, June 2010.

   [RFC6370]  Bocci, M., Swallow, G., and E. Gray, "MPLS Transport
              Profile (MPLS-TP) Identifiers", RFC 6370, September 2011.

   [RFC6374]  Frost, D. and S. Bryant, "Packet Loss and Delay
              Measurement for MPLS Networks", RFC 6374, September 2011.

   [RFC6375]  Frost, D.

   [RFC6427]  Swallow, G., Fulignoli, A., Vigoureux, M., Boutros, S.,
              and S. Bryant, "A Packet Loss D. Ward, "MPLS Fault Management Operations,
              Administration, and Delay
              Measurement Profile for MPLS-Based Transport Networks", Maintenance (OAM)", RFC 6375, September 6427,
              November 2011.

   [RFC6428]  Allan, D., Swallow Ed. , G., and J. Drake Ed. , "Proactive
              Connectivity Verification, Continuity Check, and Remote
              Defect Indication for the MPLS Transport Profile",
              RFC 6428, November 2011.

8.2.  Informative References

   [BFD-CCCV]
              Allan, D., Swallow, G., and J. Drake, "Proactive
              Connectivity Verification, Continuity Check and Remote
              Defect indication for MPLS Transport Profile", 2010,
              <draft-ietf-mpls-tp-bfd-cc-cv-rdi>.

   [BFD-Ping]
              Bahadur, N., Aggarwal, R., Ward, D., Nadeau, T., Sprecher,
              N., and Y. Weingarten, "LSP Ping and BFD encapsulation
              over ACH", 2010,
              <draft-ietf-mpls-tp-lsp-ping-bfd-procedures-02>.

   [ETH-OAM]  Takacs, A., Gero, B., Fedyk, D., Mohan, D., and D. H. Long, "GMPLS RSVP-TE
              Extensions for Ethernet OAM", 2009, OAM Configuration", 2012,
              <draft-ietf-ccamp-rsvp-te-eth-oam-ext>.

   [LSP-PING-CONF]
              Bellagamba, E., Andersson, L., Ward, D., Drake, J., and P.
              Skoldstrom, "Configuration of pro-active MPLS-TP
              Operations, Administration, and Maintenance (OAM)
              Functions Using LSP Ping", 2010, 2012,
              <draft-ietf-mpls-lsp-ping-mpls-tp-oam-conf>.

   [MPLS-TP-OAM-Analysis]
              Sprecher, N., Weingarten, Y., and E. Bellagamba, "MPLS-TP
              OAM Analysis", 2011, <draft-ietf-mpls-tp-oam-analysis>.

   [MPLS-TP-OAM-FWK]
              Bocci, M. and D. Allan, "Operations, Administration and
              Maintenance Framework for MPLS-based Transport Networks",
              2010, <draft-ietf-mpls-tp-oam-framework>.

   [RFC4379]  Kompella, K. and G. Swallow, "Detecting Multi-Protocol
              Label Switched (MPLS) Data Plane Failures", RFC 4379,
              February 2006.

   [RFC4447]  Martini, L., Rosen, E., El-Aawar, N., Smith, T., and G.
              Heron, "Pseudowire Setup and Maintenance Using the Label
              Distribution Protocol (LDP)", RFC 4447, April 2006.

   [RFC5921]  Bocci, M., Bryant, S., Frost, D., Levrau, L., and L.
              Berger, "A Framework for MPLS in Transport Networks",
              RFC 5921, July 2010.

   [RFC6371]  Busi, I. and D. Allan, "Operations, Administration, and
              Maintenance Framework for MPLS-Based Transport Networks",
              RFC 6371, September 2011.

   [RFC6375]  Frost, D. and S. Bryant, "A Packet Loss and Delay
              Measurement Profile for MPLS-Based Transport Networks",
              RFC 6375, September 2011.

   [RFC6435]  Boutros, S., Sivabalan, S., Aggarwal, R., Vigoureux, M.,
              and X. Dai, "MPLS Transport Profile Lock Instruct and
              Loopback Functions", RFC 6435, November 2011.

   [RFC6669]  Sprecher, N. and L. Fang, "An Overview of the Operations,
              Administration, and Maintenance (OAM) Toolset for MPLS-
              Based Transport Networks", RFC 6669, July 2012.

Authors' Addresses

   Elisa Bellagamba (editor)
   Ericsson
   Torshamnsgatan 48
   Kista,   164 40
   Sweden

   Email: elisa.bellagamba@ericsson.com

   Loa Andersson (editor)
   Ericsson
   Torshamnsgatan 48
   Kista,   164 40
   Sweden

   Phone:
   Email: loa.andersson@ericsson.com

   Pontus Skoldstrom (editor)
   Acreo AB
   Electrum 236
   Kista,   164 40
   Sweden

   Phone: +46 8 6327731
   Email: pontus.skoldstrom@acreo.se

   Dave Ward
   Juniper
   Cisco

   Phone:
   Email: dward@juniper.net dward@cisco.com

   Attila Takacs
   Ericsson
   1. Laborc u.
   Budapest,
   HUNGARY

   Phone:
   Email: attila.takacs@ericsson.com