--- 1/draft-ietf-pce-association-diversity-02.txt 2018-02-27 06:13:18.240687757 -0800 +++ 2/draft-ietf-pce-association-diversity-03.txt 2018-02-27 06:13:18.284688795 -0800 @@ -1,24 +1,24 @@ PCE Working Group S. Litkowski Internet-Draft Orange Intended status: Standards Track S. Sivabalan -Expires: March 15, 2018 Cisco Systems, Inc. +Expires: August 31, 2018 Cisco Systems, Inc. C. Barth Juniper Networks D. Dhody Huawei - September 11, 2017 + February 27, 2018 Path Computation Element communication Protocol extension for signaling LSP diversity constraint - draft-ietf-pce-association-diversity-02 + draft-ietf-pce-association-diversity-03 Abstract This document introduces a simple mechanism to associate a group of Label Switched Paths (LSPs) via an extension to the Path Computation Element Communication Protocol (PCEP) with the purpose of computing diverse paths for those LSPs. The proposed extension allows a PCC to advertise to a PCE the belonging of a particular LSP to a disjoint- group, thus the PCE knows that LSPs in the same group must be disjoint from each other. @@ -31,89 +31,89 @@ Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." - This Internet-Draft will expire on March 15, 2018. + This Internet-Draft will expire on August 31, 2018. Copyright Notice - Copyright (c) 2017 IETF Trust and the persons identified as the + 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 to this document. Code Components extracted from this document must 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 . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. Motivation . . . . . . . . . . . . . . . . . . . . . . . . . 4 4. Protocol extension . . . . . . . . . . . . . . . . . . . . . 7 4.1. Association group . . . . . . . . . . . . . . . . . . . . 7 - 4.2. Mandatory TLV . . . . . . . . . . . . . . . . . . . . . . 7 - 4.3. Optional TLVs . . . . . . . . . . . . . . . . . . . . . . 9 - 4.4. Disjointness objective functions . . . . . . . . . . . . 9 - 4.5. P-flag considerations . . . . . . . . . . . . . . . . . . 9 - 4.6. Disjointness computation issues . . . . . . . . . . . . . 12 - 5. Security Considerations . . . . . . . . . . . . . . . . . . . 13 - 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13 - 6.1. Association object Type Indicators . . . . . . . . . . . 13 - 6.2. PCEP TLVs . . . . . . . . . . . . . . . . . . . . . . . . 14 - 6.3. NO-PATH-VECTOR bit Flags . . . . . . . . . . . . . . . . 14 - 6.4. PCEP-ERROR codes . . . . . . . . . . . . . . . . . . . . 14 - 7. Manageability Considerations . . . . . . . . . . . . . . . . 15 - 7.1. Control of Function and Policy . . . . . . . . . . . . . 15 - 7.2. Information and Data Models . . . . . . . . . . . . . . . 15 - 7.3. Liveness Detection and Monitoring . . . . . . . . . . . . 15 - 7.4. Verify Correct Operations . . . . . . . . . . . . . . . . 15 - 7.5. Requirements On Other Protocols . . . . . . . . . . . . . 15 - 7.6. Impact On Network Operations . . . . . . . . . . . . . . 15 - 8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 15 - 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 16 - 9.1. Normative References . . . . . . . . . . . . . . . . . . 16 - 9.2. Informative References . . . . . . . . . . . . . . . . . 16 - Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17 + 4.2. Mandatory TLV . . . . . . . . . . . . . . . . . . . . . . 8 + 4.3. Optional TLVs . . . . . . . . . . . . . . . . . . . . . . 10 + 4.4. Disjointness objective functions . . . . . . . . . . . . 10 + 4.5. P-flag considerations . . . . . . . . . . . . . . . . . . 11 + 4.6. Disjointness computation issues . . . . . . . . . . . . . 14 + 5. Security Considerations . . . . . . . . . . . . . . . . . . . 15 + 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15 + 6.1. Association object Type Indicators . . . . . . . . . . . 15 + 6.2. PCEP TLVs . . . . . . . . . . . . . . . . . . . . . . . . 15 + 6.3. Objective Functions . . . . . . . . . . . . . . . . . . . 16 + 6.4. NO-PATH-VECTOR bit Flags . . . . . . . . . . . . . . . . 16 + 6.5. PCEP-ERROR codes . . . . . . . . . . . . . . . . . . . . 16 + 7. Manageability Considerations . . . . . . . . . . . . . . . . 16 + 7.1. Control of Function and Policy . . . . . . . . . . . . . 16 + 7.2. Information and Data Models . . . . . . . . . . . . . . . 17 + 7.3. Liveness Detection and Monitoring . . . . . . . . . . . . 17 + 7.4. Verify Correct Operations . . . . . . . . . . . . . . . . 17 + 7.5. Requirements On Other Protocols . . . . . . . . . . . . . 17 + 7.6. Impact On Network Operations . . . . . . . . . . . . . . 17 + 8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 17 + 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 17 + 9.1. Normative References . . . . . . . . . . . . . . . . . . 17 + 9.2. Informative References . . . . . . . . . . . . . . . . . 18 + Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18 1. Introduction [RFC5440] describes the Path Computation Element communication Protocol (PCEP) which enables the communication between a Path Computation Client (PCC) and a Path Control Element (PCE), or between two PCEs based on the PCE architecture [RFC4655]. - PCEP Extensions for Stateful PCE Model [I-D.ietf-pce-stateful-pce] - describes a set of extensions to PCEP to enable active control of - MPLS-TE and GMPLS tunnels. [I-D.ietf-pce-pce-initiated-lsp] - describes the setup and teardown of PCE-initiated LSPs under the - active stateful PCE model, without the need for local configuration - on the PCC, thus allowing for a dynamic network. + PCEP Extensions for Stateful PCE Model [RFC8231] describes a set of + extensions to PCEP to enable active control of MPLS-TE and GMPLS + tunnels. [RFC8281] describes the setup and teardown of PCE-initiated + LSPs under the active stateful PCE model, without the need for local + configuration on the PCC, thus allowing for a dynamic network. [I-D.ietf-pce-association-group] introduces a generic mechanism to create a grouping of LSPs which can then be used to define associations between a set of LSPs and a set of attributes (such as configuration parameters or behaviours) and is equally applicable to - the active and passive modes of a stateful PCE - [I-D.ietf-pce-stateful-pce] or a stateless PCE [RFC5440]. + the active and passive modes of a stateful PCE [RFC8231] or a + stateless PCE [RFC5440]. This document specifies a PCEP extension to signal that a particular group of LSPs should use diverse paths including the requested type of diversity. A PCC can use this extension to signal to a PCE the belonging of a particular LSP to a disjoint-group. When a PCE receives LSP states belonging to the same disjoint-group from some PCCs, the PCE should ensure that the LSPs within the group are disjoint from each other. 1.1. Requirements Language @@ -193,32 +193,51 @@ Figure 1 - Disjoint paths with different head-ends and tail-ends In the figure above, the customer wants to have two disjoint paths between CE1/CE2 and CE3/CE4. From an IP/MPLS network point view, in this example, the CEs are connected to different PEs to maximize their disjointness. When LSPs originate from different head-ends, distributed computation of diverse paths can be difficult. Whereas, computation via a centralized PCE ensures path disjointness correctness and simplicity. - The SVEC (Synchronization VECtor) object [RFC5440] allows a PCC to - request the synchronization of a set of dependent or independent path - computation requests. As per [RFC5440], the SVEC object is optional - and may be carried within a PCReq message. It uses the Request-ID- - number carried within the respective RP (Request Parameters) object - to identify the computation request that should be syncronized. + [RFC5440] defines a mechanism for the synchronization of a set of + path computation requests by using the SVEC (Synchronization VECtor) + object, that specifies the list of synchronized requests that can + either be dependent or independent. The SVEC object identify the + relationship between the set of path computation requests, identified + by 'Request-ID-number' in RP (Request Parameters) object. [RFC6007] + further clarifies the use of the SVEC list for synchronized path + computations when computing dependent requests as well as describes a + number of usage scenarios for SVEC lists within single-domain and + multi-domain environments. - The PCEP extension for stateful PCE [I-D.ietf-pce-stateful-pce] - defined new PCEP messages - PCRpt, PCUpd and PCInitiate. These - messages uses PLSP-ID in the LSP object for identification. Moreover - to allow diversity between LSPs originating from different PCCs, the - generic mechanism to create a grouping of LSPs as described in + The SVEC object includes a Flags field that indicates the potential + dependency between the set of path computation request in a similar + way as the Flags field in the TLVs defined in this document. The + path computation request (PCReq) message MAY use both SVEC object to + identify the related path computation request as well as to identify + the diversity association group. The PCE MUST try to find a path + that meets both the constraints. It is possible that the diversity + set in the association group is different from the one in SVEC + object, this might be true for the same LSP as well. The PCE would + consider both the objects as per the processing rules and aim to find + a path that meets both these constraints. In case no such path is + possible (or the constraints are incompatible), the PCE MUST send a + path computation reply (PCRep) with NO-PATH object indicating path + computation failure as per [RFC5440]. + + The PCEP extension for stateful PCE [RFC8231] defined new PCEP + messages - PCRpt, PCUpd and PCInitiate. These messages uses PLSP-ID + in the LSP object for identification. Moreover to allow diversity + between LSPs originating from different PCCs, the generic mechanism + to create a grouping of LSPs as described in [I-D.ietf-pce-association-group] equally applicable to the active and passive modes of a stateful PCE is better suited. Using PCEP, the PCC MUST indicate that disjoint path computation is required, such indication SHOULD include disjointness parameters such as the type of disjointness, the disjoint group-id, and any customization parameters according to the configured local policy. As mentioned previously, the extension described in [I-D.ietf-pce-association-group] is well suited to associated a set of LSPs with a particular disjoint-group. @@ -230,26 +249,26 @@ limitation. For example, when a PCC or PCE initiates all the LSPs in a particular disjoint-group, it can set the IPv4/IPv6 association source can be set to one of its IP address. When disjoint LSPs are initiated from different head-ends, a unique association identifier SHOULD be used for those LSPs: this can be achieved by setting the IPv4/IPv6 source address to a common value (zero value can be used) as well as the Association ID. Initiate & Monitor LSP | - | PCReq + | PCReq/PCRpt V {Disjoint-group Y} +-----+ ----------------> +-----+ _ _ _ _ _ _| PCE | | | PCE | | +-----+ | ----------> +-----+ - | PCInitiate | | PCReq + | PCInitiate | | PCReq/PCRpt |{Disjoint-group X} | | {Disjoint-group Y} | | | | .-----. | | .-----. | ( ) | +----+ ( ) | .--( )--. | |PE 1|--.--( )--. V ( ) | +----+ ( ) +---+ ( ) | ( ) |PCC|----( (G)MPLS network ) +----+ ( (G)MPLS network ) +---+ ( ) |PE 3|------( ) Disjoint-group X ) +----+ ( ) @@ -275,23 +294,25 @@ 4. Protocol extension 4.1. Association group As per [I-D.ietf-pce-association-group], LSPs are associated with other LSPs with which they interact by adding them to a common association group. The Association ID will be used to identify the disjoint group a set of LSPs belongs to. This document defines a new Association type, based on the generic Association object - - o Association type = TBD1 ("Disjointness Association Type"). + The association type is considered to be both dynamic and operator- + configured. + A disjoint group can have two or more LSPs. But a PCE may be limited in how many LSPs it can take into account when computing disjointness. If a PCE receives more LSPs in the group than it can handle in its computation algorithm, it SHOULD apply disjointness computation to only a subset of LSPs in the group. The subset of disjoint LSPs will be decided by the implementation. Local polices on the PCC or PCE MAY define the computational behavior for the other LSPs in the group. For example, the PCE may provide no path, a shortest path, or a constrained path based on relaxing @@ -299,24 +320,30 @@ Associating a particular LSP to multiple disjoint groups is authorized from a protocol perspective, however there is no insurance that the PCE will be able to compute properly the multi-disjointness constraint. 4.2. Mandatory TLV The disjoint group MUST carry the following TLV: - o DISJOINTNESS-INFORMATION-TLV: Used to communicate some - disjointness specific parameters. + o DISJOINTNESS-CONFIGURATION-TLV: Used to communicate some + disjointness configuration parameters. - The DISJOINTNESS-INFORMATION-TLV is shown in the following figure: + In addition, the disjoint group MAY carry the following TLV in a + PCUpd or PCRep message: + + o DISJOINTNESS-STATUS-TLV: Used to communicate the status of the + computed disjointness. + + The DISJOINTNESS-CONFIGURATION-TLV is shown in the following figure: 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 = [TBD2] | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Flags |T|P|S|N|L| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Flags: @@ -347,42 +374,108 @@ * T (Strict disjointness) bit: when set, if disjoint paths cannot be found, PCE should return no path for LSPs that could not be be disjoint. When unset, PCE is allowed to relax disjointness by using either applying a requested objective function or any other behavior if no objective function is requested (e.g.: using a lower disjoint type (link instead of node) or relaxing disjointness constraint at all). If a PCEP speaker receives a disjoint-group without DISJOINTNESS- - INFORMATION-TLV, it SHOULD reply with a PCErr Error-type=6 (Mandatory - Object missing) and Error-value=TBD7. + CONFIGURATION-TLV, it SHOULD reply with a PCErr Error-type=6 + (Mandatory Object missing) and Error-value=TBD7. + + The DISJOINTNESS-STATUS-TLV uses the same format as the DISJOINTNESS- + CONFIGURATION-TLV with a different type: + + 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 = [TBD3] | Length | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Flags |T|P|S|N|L| + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Any new flag defined for the DISJOINTNESS-CONFIGURATION-TLV MUST be + automatically added to the DISJOINTNESS-STATUS-TLV. 4.3. Optional TLVs The disjoint group MAY carry some optional TLVs including but not limited to: o VENDOR-INFORMATION-TLV: Used to communicate arbitrary vendor specific behavioral information, described in [RFC7150]. 4.4. Disjointness objective functions An objective function MAY be applied to the disjointness computation to drive the PCE computation behavior. In this case, the OF-List TLV (defined in ([RFC5541]) is used as an optional TLV in the Association Group Object. The PCEP OF-List TLV allow multiple OF-Codes inside the TLV, a sender SHOULD include a single OF-Code in the OF-List TLV when included in the Association Group, and the receiver MUST - consider the first OF-code only and ignore others if included. The - OF-Code to maximize diversity are specified in - ([I-D.dhody-pce-of-diverse]). + consider the first OF-code only and ignore others if included. + + To minimize the common shared resources (Node, Link or SRLG) between + a set of paths during path computation three new OF codes are + proposed: + + MSL + + * Name: Minimize the number of shared (common) Links. + + * Objective Function Code: TBD4 + + * Description: Find a set of paths such that it passes through the + least number of shared (common) links. + + MSS + + * Name: Minimize the number of shared (common) SRLGs. + + * Objective Function Code: TBD5 + + * Description: Find a set of paths such that it passes through the + least number of shared (common) SRLGs. + + MSN + + * Name: Minimize the number of shared (common) Nodes. + + * Objective Function Code: TBD6 + * Description: Find a set of paths such that it passes through the + least number of shared (common) nodes. + + [RFC5440] uses SVEC diversity flag for node, link or SRLG to describe + the potential disjointness between the set of path computation + requests used in PCEP protocol. + + This document defines three new OF codes to maximize diversity as + much as possible, in other words, minimize the common shared + resources (Node,Link or SRLG) between a set of paths. + + It may be interesting to note that the diversity flags in the SVEC + object and OF for diversity can be used together. Some example of + usage are listed below - + + o SVEC object with node-diverse bit=1 - ensure full node-diversity. + + o SVEC object with node-diverse bit=1 and OF=MSS - full node diverse + with as much as SRLG-diversity as possible. + + o SVEC object with domain-diverse bit=1;link diverse bit=1 and + OF=MSS - full domain and node diverse path with as much as SRLG- + diversity as possible. + + o SVEC object with node-diverse bit=1 and OF=MSN - ensure full node- + diversity. 4.5. P-flag considerations As mentioned in Section 4.2, the P-flag (when set) indicates that the computed path of the LSP SHOULD satisfies all constraints and objective functions first without considering the diversity constraint. This could be required in some primary/backup scenarios where the primary path should use the more optimal path available (taking into account the other constraints). When disjointness is computed, it is important for the algorithm to know that it should @@ -498,143 +591,136 @@ When P-flag is set for an LSP and when ECMPs are available, an implementation MAY select a path that allows disjointness. 4.6. Disjointness computation issues There may be some cases where the PCE is not able to provide a set of disjoint paths for one or more LSPs in the association. When the T-bit is set (Strict disjointness requested), if - disjointness cannot be found for one or more LSPs, the PCE SHOULD + disjointness cannot be ensured for one or more LSPs, the PCE SHOULD reply with a PCUpd message containing an empty ERO. In addition to the empty ERO Object, the PCE MAY add the NO-PATH-VECTOR TLV ([RFC5440]) in the LSP Object. This document adds new bits in the NO-PATH-VECTOR TLV: - bit "TBD3": when set, the PCE indicates that it could not find a + bit "TBD7": when set, the PCE indicates that it could not find a disjoint path for this LSP. - bit "TBD4": when set, the PCE indicates that it does not support + bit "TBD8": when set, the PCE indicates that it does not support the requested disjointness computation. - The NO-PATH-VECTOR TLV MAY also be used when T-bit is unset and when - the PCE cannot provide a path for an LSP in the disjoint group. - - When the T-bit is unset, the PCE is allowed to relax the constraint - if it cannot be satisfied. This document introduces a new RELAXED- - CONSTRAINT-TLV that MAY be used by a PCE to indicate that some - constraints have been relaxed. - - When used, the RELAXED-CONSTRAINT-TLV SHOULD be included in the LSP - Object of a PCUpd message. The RELAXED-CONSTRAINT-TLV has the - following format: + When the T-bit is unset, the PCE is allowed to reduce the required + level of disjointness. The actual level of disjointness computed by + the PCE can be reported through the DISJOINTNESS-STATUS-TLV by + setting the appropriate flags in the TLV. While the DISJOINTNESS- + CONFIGURATION-TLV defines the expected level of disjointness required + by configuration, the DISJOINTNESS-STATUS-TLV defines the actual + level of disjointness computed. - 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 = [TBD5] | Length | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Object-Class#1| OT#1 |Res|P|I| Object Length (bytes) | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | | - // (Object body) // - | | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - ... - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Object-Class#n| OT#n |Res|P|I| Object Length (bytes) | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | | - // (Object body) // - | | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + There are some cases where the PCE may need to completely relax the + disjointness constraint in order to provide a path to all the LSPs + that are part of the association. A mechanism that allows the PCE to + fully relax a constraint is considered by the authors as more global + to PCEP rather than linked to the disjointness use case. As a + consequence, it is considered as out of scope of the document. All LSPs in a particular disjoint group MUST use the same combination - of T,S,N,L flags in the DISJOINTNESS-INFORMATION-TLV. If a PCE + of T,S,N,L flags in the DISJOINTNESS-CONFIGURATION-TLV. If a PCE receives PCRpt messages for LSPs belonging to the same disjoint group but having an inconsistent combination of T,S,N,L flags, the PCE SHOULD NOT try to compute disjointness path and SHOULD reply a PCErr with Error-type 5 (Policy Violation) and Error-Value TBD6 - (Inconsistent parameters in DISJOINTNESS-INFORMATION TLV) to all PCCs - involved in the disjoint group. + (Inconsistent parameters in DISJOINTNESS-CONFIGURATION TLV) to all + PCCs involved in the disjoint group. 5. Security Considerations This document defines one new type for association, which do not add any new security concerns beyond those discussed in [RFC5440], - [I-D.ietf-pce-stateful-pce] and [I-D.ietf-pce-association-group] in - itself. + [RFC8231] and [I-D.ietf-pce-association-group] in itself. 6. IANA Considerations 6.1. Association object Type Indicators This document defines the following new association type originally defined in [I-D.ietf-pce-association-group]. Value Name Reference TBD1 Disjoint-group Association Type [This I.D.] 6.2. PCEP TLVs This document defines the following new PCEP TLVs: Value Name Reference - TBD2 DISJOINTNESS-INFORMATION-TLV [This I.D.] - TBD5 RELAXED-CONSTRAINT-TLV [This I.D.] + TBD2 DISJOINTNESS-CONFIGURATION-TLV [This I.D.] + TBD3 DISJOINTNESS-STATUS-TLV [This I.D.] IANA is requested to manage the space of flags carried in the - DISJOINTNESS-INFORMATION TLV defined in this document, numbering them - from 0 as the least significant bit. + DISJOINTNESS-CONFIGURATION-TLV defined in this document, numbering + them from 0 as the least significant bit. New bit numbers may be allocated in future. IANA is requested to allocate the following bit numbers in the - DISJOINTNESS-INFORMATION-TLV flag space: + DISJOINTNESS-CONFIGURATION-TLV flag space: Bit Number Name Reference 0 Link disjointness [This I.D.] 1 Node disjointness [This I.D.] 2 SRLG disjointness [This I.D.] 3 Shortest-path [This I.D.] 4 Strict disjointness [This I.D.] -6.3. NO-PATH-VECTOR bit Flags +6.3. Objective Functions + + three new Objective Functions have been defined. IANA has made the + following allocations from the PCEP "Objective Function" sub- + registry: + + Value Description Reference + TBD4 MSL [This I.D.] + TBD5 MSN [This I.D.] + TBD6 MSS [This I.D.] + +6.4. NO-PATH-VECTOR bit Flags This documents defines new bits for the NO-PATH-VECTOR TLV in the "NO-PATH-VECTOR TLV Flag Field" sub-registry of the "Path Computation Element Protocol (PCEP) Numbers" registry: Bit Number Name Reference - TBD3 Disjoint path not found [This I.D.] + TBD7 Disjoint path not found [This I.D.] - TBD4 Requested disjointness [This I.D.] + TBD8 Requested disjointness [This I.D.] computation not supported -6.4. PCEP-ERROR codes +6.5. PCEP-ERROR codes IANA is requested to allocate new Error Types and Error Values within the " PCEP-ERROR Object Error Types and Values" sub-registry of the PCEP Numbers registry, as follows: Error-Type Meaning 5 Policy violation Error-value=TBD6: Inconsistent parameters - in DISJOINTNESS-INFORMATION TLV + in DISJOINTNESS-CONFIGURATION TLV 6 Mandatory Object missing - Error-value=TBD7: DISJOINTNESS-INFORMATION TLV missing + Error-value=TBD7: DISJOINTNESS-CONFIGURATION TLV missing 7. Manageability Considerations 7.1. Control of Function and Policy An operator MUST be allowed to configure the disjointness associations and parameters at PCEP peers and associate it with the LSPs. 7.2. Information and Data Models @@ -695,51 +781,46 @@ DOI 10.17487/RFC5541, June 2009, . [I-D.ietf-pce-association-group] Minei, I., Crabbe, E., Sivabalan, S., Ananthakrishnan, H., Dhody, D., and Y. Tanaka, "PCEP Extensions for Establishing Relationships Between Sets of LSPs", draft- ietf-pce-association-group-04 (work in progress), August 2017. - [I-D.ietf-pce-stateful-pce] - Crabbe, E., Minei, I., Medved, J., and R. Varga, "PCEP - Extensions for Stateful PCE", draft-ietf-pce-stateful- - pce-21 (work in progress), June 2017. - - [I-D.dhody-pce-of-diverse] - Dhody, D. and Q. Wu, "PCE support for Maximizing - Diversity", draft-dhody-pce-of-diverse-07 (work in - progress), May 2017. + [RFC8231] Crabbe, E., Minei, I., Medved, J., and R. Varga, "Path + Computation Element Communication Protocol (PCEP) + Extensions for Stateful PCE", RFC 8231, + DOI 10.17487/RFC8231, September 2017, + . 9.2. Informative References [RFC7150] Zhang, F. and A. Farrel, "Conveying Vendor-Specific Constraints in the Path Computation Element Communication Protocol", RFC 7150, DOI 10.17487/RFC7150, March 2014, . [RFC7420] Koushik, A., Stephan, E., Zhao, Q., King, D., and J. Hardwick, "Path Computation Element Communication Protocol (PCEP) Management Information Base (MIB) Module", RFC 7420, DOI 10.17487/RFC7420, December 2014, . - [I-D.ietf-pce-pce-initiated-lsp] - Crabbe, E., Minei, I., Sivabalan, S., and R. Varga, "PCEP - Extensions for PCE-initiated LSP Setup in a Stateful PCE - Model", draft-ietf-pce-pce-initiated-lsp-10 (work in - progress), June 2017. + [RFC8281] Crabbe, E., Minei, I., Sivabalan, S., and R. Varga, "Path + Computation Element Communication Protocol (PCEP) + Extensions for PCE-Initiated LSP Setup in a Stateful PCE + Model", RFC 8281, DOI 10.17487/RFC8281, December 2017, + . Authors' Addresses - Stephane Litkowski Orange EMail: stephane.litkowski@orange.com Siva Sivabalan Cisco Systems, Inc. 2000 Innovation Drive Kanata, Ontario K2K 3E8 Canada