[Docs] [txt|pdf|xml|html] [Tracker] [Email] [Diff1] [Diff2] [Nits]

Versions: 00 01 02 03 04 05 draft-ietf-pce-stateful-path-protection

PCE Working Group                                     H. Ananthakrishnan
Internet-Draft                                             Packet Design
Intended status: Standards Track                            S. Sivabalan
Expires: December 31, 2017                                         Cisco
                                                                C. Barth
                                                                R. Torvi
                                                        Juniper Networks
                                                                I. Minei
                                                             Google, Inc
                                                               E. Crabbe
                                                  Individual Contributor
                                                                D. Dhody
                                                     Huawei Technologies
                                                           June 29, 2017


   PCEP Extensions for MPSL-TE LSP Path Protection with stateful PCE
         draft-ananthakrishnan-pce-stateful-path-protection-03

Abstract

   A stateful Path Computation Element (PCE) is capable of computing as
   well as controlling via Path Computation Element Protocol (PCEP)
   Multiprotocol Label Switching Traffic Engineering Label Switched
   Paths (MPLS LSP).  Furthermore, it is also possible for a stateful
   PCE to create, maintain, and delete LSPs.  This document describes
   PCEP extension to associate two or more LSPs to provide end-to-end
   path protection.

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
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://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 December 31, 2017.






Ananthakrishnan, et al. Expires December 31, 2017               [Page 1]


Internet-Draft      Stateful PCE LSP Path Protection           June 2017


Copyright Notice

   Copyright (c) 2017 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
   (http://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  . . . . . . . . . . . . . . . . . . . . . . . .   3
     1.1.  Requirements Language . . . . . . . . . . . . . . . . . .   4
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   4
   3.  PCEP Extensions . . . . . . . . . . . . . . . . . . . . . . .   4
     3.1.  Path Protection Association Type  . . . . . . . . . . . .   4
     3.2.  Path Protection Association TLV . . . . . . . . . . . . .   5
   4.  Operation . . . . . . . . . . . . . . . . . . . . . . . . . .   6
     4.1.  PCC Initiated LSPs  . . . . . . . . . . . . . . . . . . .   6
     4.2.  PCE Initiated LSPs  . . . . . . . . . . . . . . . . . . .   7
     4.3.  State Synchronization . . . . . . . . . . . . . . . . . .   7
     4.4.  Error Handling  . . . . . . . . . . . . . . . . . . . . .   7
   5.  Other considerations  . . . . . . . . . . . . . . . . . . . .   7
   6.  IANA considerations . . . . . . . . . . . . . . . . . . . . .   7
     6.1.  Association Type  . . . . . . . . . . . . . . . . . . . .   8
     6.2.  PPAG TLV  . . . . . . . . . . . . . . . . . . . . . . . .   8
     6.3.  PCEP Errors . . . . . . . . . . . . . . . . . . . . . . .   9
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .   9
   8.  Manageability Considerations  . . . . . . . . . . . . . . . .  10
     8.1.  Control of Function and Policy  . . . . . . . . . . . . .  10
     8.2.  Information and Data Models . . . . . . . . . . . . . . .  10
     8.3.  Liveness Detection and Monitoring . . . . . . . . . . . .  10
     8.4.  Verify Correct Operations . . . . . . . . . . . . . . . .  10
     8.5.  Requirements On Other Protocols . . . . . . . . . . . . .  10
     8.6.  Impact On Network Operations  . . . . . . . . . . . . . .  10
   9.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .  10
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .  11
     10.1.  Normative References . . . . . . . . . . . . . . . . . .  11
     10.2.  Information References . . . . . . . . . . . . . . . . .  11
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  12





Ananthakrishnan, et al. Expires December 31, 2017               [Page 2]


Internet-Draft      Stateful PCE LSP Path Protection           June 2017


1.  Introduction

   [RFC5440] describes PCEP for communication between a Path Computation
   Client (PCC) and a PCE or between one a pair of PCEs as per
   [RFC4655].  A PCE computes paths for MPLS-TE LSPs based on various
   constraints and optimization criteria.

   Stateful pce [I-D.ietf-pce-stateful-pce] specifies a set of
   extensions to PCEP to enable stateful control of paths such as MPLS
   TE LSPs between and across PCEP sessions in compliance with
   [RFC4657].  It includes mechanisms to effect LSP state
   synchronization between PCCs and PCEs, delegation of control of LSPs
   to PCEs, and PCE control of timing and sequence of path computations
   within and across PCEP sessions and focuses on a model where LSPs are
   configured on the PCC and control over them is delegated to the PCE.
   Furthermore, a mechanism to dynamically instantiate LSPs on a PCC
   based on the requests from a stateful PCE or a controller using
   stateful PCE is specified in [I-D.ietf-pce-pce-initiated-lsp].

   Path protection refers to a paradigm in which the working LSP is
   protected by one or more protection LSP(s).  When the working LSP
   fails, protection LSP(s) is/are activated.  When the working LSPs are
   computed and controlled by the PCE, there is benefit in a mode of
   operation where protection LSPs are as well.

   This document specifies a stateful PCEP extension to associate two or
   more LSPs for the purpose of setting up path protection.  The
   proposed extension covers the following scenarios:

   o  A PCC initiates a protection LSP and retains the control of the
      LSP.  The PCC computes the path himself or make a request for path
      computation to a PCE.  After the path setup, it reports to the PCE
      with the information and state of the path.  This is the passive
      stateful mode [RFC8051].

   o  A PCC initiates a protection LSP and delegates the control of the
      LSP to a stateful PCE.  The PCE may compute the path for the LSP
      and update the PCC with the information about the path as long as
      it controls the LSP.  This is the active stateful mode [RFC8051].

   o  A protection LSP could be initiated by a stateful PCE, which
      retains the control of the LSP.  The PCE is responsible for
      computing the path of the LSP and updating to the PCC with the
      information about the path.  This is the PCE Initiated mode
      [I-D.ietf-pce-pce-initiated-lsp].

   Note that protection LSP can be established prior to the failure (in
   which case the LSP is said to me in standby mode) or post failure of



Ananthakrishnan, et al. Expires December 31, 2017               [Page 3]


Internet-Draft      Stateful PCE LSP Path Protection           June 2017


   the corresponding working LSP according to the operator choice/
   policy.

1.1.  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 [RFC2119].

2.  Terminology

   The following terminologies are used in this document:

   ERO:  Explicit Route Object.

   LSP:  Label Switched Path.

   PCC:  Path Computation Client.

   PCE:  Path Computation Element

   PCEP:  Path Computation Element Protocol.

   PPAG:  Path Protection Association Group.

   TLV:  Type, Length, and Value.

3.  PCEP Extensions

3.1.  Path Protection Association Type

   LSPs are not associated by listing the other LSPs with which they
   interact, but rather by making them belong to an association group
   referred to as "Path Protection Association Group" (PPAG) in this
   document.  All LSPs join a PPAG individually.  PPAG is based on the
   generic Association object used to associate two or more LSPs
   specified in [I-D.ietf-pce-association-group].  A member of a PPAG
   can take the role of working or protection LSP.  This document
   defines a new association type called "Path Protection Association
   Type" of value TBD1.  A PPAG can have one working LSP and/or one or
   more protection LSPs.  The source and destination of all LSPs within
   a PPAG MUST be the same.

   The format of the Association object used for PPAG is specified in
   [I-D.ietf-pce-association-group] and replicated in this document for
   easy reference in Figure 1 and Figure 2.





Ananthakrishnan, et al. Expires December 31, 2017               [Page 4]


Internet-Draft      Stateful PCE LSP Path Protection           June 2017


      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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |         Reserved            |              Flags            |R|
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Association type = TBD1    |          Association            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                IPv4 Association Source                        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      //            Optional TLVs                                    //
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


               Figure 1: PPAG IPv4 ASSOCIATION Object format

     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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |         Reserved            |              Flags            |R|
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     | Association Type = TBD1     |          Association            |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                                                               |
     |                IPv6 Association Source                        |
     |                                                               |
     |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     //            Optional TLVs                                    //
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


               Figure 2: PPAG IPv6 ASSOCIATION Object format

   This document defines a new Association type, the Path Protection
   Association type, value will be assigned by IANA (TBD1).

   This Association-Type is dynamic in nature and created by the PCC or
   PCE for the LSPs originating at the same head node and terminating at
   the same destination.  These associations are conveyed via PCEP
   messages to the PCEP peer.  Operator-configured Association Range
   SHOULD NOT be set for this association-type and MUST be ignored.

3.2.  Path Protection Association TLV

   The Path Protection Association TLV is an optional TLV for use with
   the Path Protection Association Object Type.  The Path Protection
   Association TLV MUST NOT be present more than once.  If it appears




Ananthakrishnan, et al. Expires December 31, 2017               [Page 5]


Internet-Draft      Stateful PCE LSP Path Protection           June 2017


   more than once, only the first occurrence is processed and any others
   MUST be ignored.

   The Path Protection Association TLV follows the PCEP TLV format of
   [RFC5440].

   The type (16 bits) of the TLV is to be assigned by IANA.  The length
   field is 16 bit-long and has a fixed value of 4.

   The value comprises a single field, the Path Protection Association
   Flags (32 bits), where each bit represents a flag option.

   The format of the Path Protection Association TLV (Figure 3) is as
   follows:

     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             |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |          Path Protection Association Flags                |S|P|
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


             Figure 3: Path Protection Association TLV format

   P (PROTECTION-LSP 1 bit) - Indicates whether the LSP associated with
   the PPAG is working or protection LSP.  If this flag is set, the LSP
   is a protection LSP.

   S (STANDBY 1 bit)- When the P flag is set, the S flag indicates
   whether the protection LSP associated with the PPAG is in standby
   mode.  The S flag is ignored if the P flag is not set.

   If the Path Protection Association TLV is missing, it means the LSP
   is the working LSP.

4.  Operation

4.1.  PCC Initiated LSPs

   A PCC can associate a set of LSPs under its control for path
   protection purpose.  Similarly, the PCC can remove on or more LSPs
   under its control from the corresponding PPAG.  In both cases, the
   PCC must report the change in association to PCE(s) via PCRpt
   message.  A PCC can also delegate the working and protection LSPs to
   a stateful PCE, where PCE would control and update the paths and
   attributes of the LSPs in the association group.



Ananthakrishnan, et al. Expires December 31, 2017               [Page 6]


Internet-Draft      Stateful PCE LSP Path Protection           June 2017


   A stateless PCC can request protection to a PCE through PCReq
   message.

4.2.  PCE Initiated LSPs

   A PCE can create/update working and protection LSPs independently.
   As specified in [I-D.ietf-pce-association-group], Association Groups
   can be created by both PCE and PCC.

   A PCE can remove a protection LSP from a PPAG as specified in
   [I-D.ietf-pce-association-group].

4.3.  State Synchronization

   During state synchronization, a PCC MUST report all the existing path
   protection association groups as well as any path protection flags to
   PCE(s).  Following the state synchronization, the PCE would remove
   all stale information as per [I-D.ietf-pce-association-group].

4.4.  Error Handling

   All LSPs (working or protection) within a PPAG MUST have the same
   source and destination.  If a PCE attempts to add an LSP to a PPAG
   and the source and/or destination of the LSP is/are different from
   the LSP(s) in the PPAG, the PCC MUST send PCErr with Error-Type= TBD
   (Association Error) [I-D.ietf-pce-association-group] and Error-Value
   = TBD3 (End points mismatch for Path Protection Association).

   There MUST be only one working LSP within a PPAG.  If a PCEP Speaker
   attempts to add another working LSP, the PCEP peer MUST send PCErr
   with Error-Type=TBD (Association Error)
   [I-D.ietf-pce-association-group] and Error-Value = TBD4 (Attempt to
   add another working LSP for Path Protection Association).

5.  Other considerations

   The diversity requirement for a group of LSPs is handled via another
   association type called "Disjointness Association", as described in
   [I-D.ietf-pce-association-diversity].  The diversity requirements for
   the the protection LSP are also handled by including both ASSOCIATION
   object for the group of LSPs.

6.  IANA considerations








Ananthakrishnan, et al. Expires December 31, 2017               [Page 7]


Internet-Draft      Stateful PCE LSP Path Protection           June 2017


6.1.  Association Type

   This document defines a new association type, originally defined in
   [I-D.ietf-pce-association-group], for path protection.  IANA is
   requested to make the assignment of a new value for the sub-registry
   "ASSOCIATION Type Field" (request to be created in
   [I-D.ietf-pce-association-group]), as follows:

   +------------------------+------------------------+-----------------+
   | Association Type Value | Association Name       | Reference       |
   +------------------------+------------------------+-----------------+
   | TBD1 (Suggested value  | Path Protection        | This            |
   | - 1)                   | Association            | document        |
   +------------------------+------------------------+-----------------+

6.2.  PPAG TLV

   This document defines a new TLV for carrying additional information
   of LSPs within a path protection association group.  IANA is
   requested to make the assignment of a new value for the existing
   "PCEP TLV Type Indicators" registry as follows:

   +-----------------------+-----------------------------+-------------+
   | TLV Type Value        | TLV Name                    | Reference   |
   +-----------------------+-----------------------------+-------------+
   | TBD2 (suggested Value | Path Protection Association | This        |
   | - 29)                 | Group TLV                   | document    |
   +-----------------------+-----------------------------+-------------+

   This document requests that a new sub-registry, named "Path
   protection Association Group TLV Flag Field", is created within the
   "Path Computation Element Protocol (PCEP) Numbers" registry to manage
   the Flag field in the Path Protection Association Group TLV.  New
   values are to be assigned by Standards Action [RFC8126].  Each bit
   should be tracked with the following qualities:

   Each bit should be tracked with the following qualities:

   o  Bit number (count from 0 as the most significant bit)

   o  Name flag

   o  Reference








Ananthakrishnan, et al. Expires December 31, 2017               [Page 8]


Internet-Draft      Stateful PCE LSP Path Protection           June 2017


           +------------+--------------------+----------------+
           | Bit Number |        Name        |   Reference    |
           +------------+--------------------+----------------+
           |     31     | P - PROTECTION-LSP | This document  |
           |     30     |    S - STANDBY     | This document  |
           +------------+--------------------+----------------+

                             Table 1: PPAG TLV

6.3.  PCEP Errors

   This document defines new Error-Type and Error-Value related to path
   protection association.  IANA is requested to allocate new error
   values within the "PCEP-ERROR Object Error Types and Values" sub-
   registry of the PCEP Numbers registry, as follows:

   +------------+-------------------+----------------------------------+
   | Error-Type | Meaning           | Reference                        |
   +------------+-------------------+----------------------------------+
   | TBD        | Association error | [I-D.ietf-pce-association-group] |
   |            | Error-value=TBD3: | This document                    |
   |            | End points        |                                  |
   |            | mismatch for Path |                                  |
   |            | Protection        |                                  |
   |            | Association       |                                  |
   |            | Error-value=TBD4: | This document                    |
   |            | Attempt to add    |                                  |
   |            | another working   |                                  |
   |            | LSP for Path      |                                  |
   |            | Protection        |                                  |
   |            | Association       |                                  |
   +------------+-------------------+----------------------------------+

7.  Security Considerations

   The security considerations described in [I-D.ietf-pce-stateful-pce],
   [I-D.ietf-pce-pce-initiated-lsp], and [RFC5440] apply to the
   extensions described in this document as well.  Additional
   considerations related to associations where a malicious PCEP speaker
   could be spoofed and could be used as an attack vector by creating
   associations is described in [I-D.ietf-pce-association-group].  Thus
   securing the PCEP session using Transport Layer Security (TLS)
   [I-D.ietf-pce-pceps], as per the recommendations and best current
   practices in [RFC7525], is RECOMMENDED.







Ananthakrishnan, et al. Expires December 31, 2017               [Page 9]


Internet-Draft      Stateful PCE LSP Path Protection           June 2017


8.  Manageability Considerations

8.1.  Control of Function and Policy

   Mechanisms defined in this document do not imply any control or
   policy requirements in addition to those already listed in [RFC5440],
   [I-D.ietf-pce-stateful-pce], and [I-D.ietf-pce-pce-initiated-lsp].

8.2.  Information and Data Models

   [RFC7420] describes the PCEP MIB, there are no new MIB Objects for
   this document.

   The PCEP YANG module [I-D.ietf-pce-pcep-yang] supports associations.

8.3.  Liveness Detection and Monitoring

   Mechanisms defined in this document do not imply any new liveness
   detection and monitoring requirements in addition to those already
   listed in [RFC5440], [I-D.ietf-pce-stateful-pce], and
   [I-D.ietf-pce-pce-initiated-lsp].

8.4.  Verify Correct Operations

   Mechanisms defined in this document do not imply any new operation
   verification requirements in addition to those already listed in
   [RFC5440], [I-D.ietf-pce-stateful-pce], and
   [I-D.ietf-pce-pce-initiated-lsp].

8.5.  Requirements On Other Protocols

   Mechanisms defined in this document do not imply any new requirements
   on other protocols.

8.6.  Impact On Network Operations

   Mechanisms defined in this document do not have any impact on network
   operations in addition to those already listed in [RFC5440],
   [I-D.ietf-pce-stateful-pce], and [I-D.ietf-pce-pce-initiated-lsp].

9.  Acknowledgments

   We would like to thank Jeff Tantsura and Xian Zhang for their
   contributions to this document.







Ananthakrishnan, et al. Expires December 31, 2017              [Page 10]


Internet-Draft      Stateful PCE LSP Path Protection           June 2017


10.  References

10.1.  Normative References

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

   [RFC5440]  Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation
              Element (PCE) Communication Protocol (PCEP)", RFC 5440,
              DOI 10.17487/RFC5440, March 2009,
              <http://www.rfc-editor.org/info/rfc5440>.

   [RFC8126]  Cotton, M., Leiba, B., and T. Narten, "Guidelines for
              Writing an IANA Considerations Section in RFCs", BCP 26,
              RFC 8126, DOI 10.17487/RFC8126, June 2017,
              <http://www.rfc-editor.org/info/rfc8126>.

   [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.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.

   [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-03 (work in progress), June
              2017.

10.2.  Information References

   [RFC4655]  Farrel, A., Vasseur, J., and J. Ash, "A Path Computation
              Element (PCE)-Based Architecture", RFC 4655,
              DOI 10.17487/RFC4655, August 2006,
              <http://www.rfc-editor.org/info/rfc4655>.

   [RFC4657]  Ash, J., Ed. and J. Le Roux, Ed., "Path Computation
              Element (PCE) Communication Protocol Generic
              Requirements", RFC 4657, DOI 10.17487/RFC4657, September
              2006, <http://www.rfc-editor.org/info/rfc4657>.



Ananthakrishnan, et al. Expires December 31, 2017              [Page 11]


Internet-Draft      Stateful PCE LSP Path Protection           June 2017


   [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,
              <http://www.rfc-editor.org/info/rfc7420>.

   [RFC7525]  Sheffer, Y., Holz, R., and P. Saint-Andre,
              "Recommendations for Secure Use of Transport Layer
              Security (TLS) and Datagram Transport Layer Security
              (DTLS)", BCP 195, RFC 7525, DOI 10.17487/RFC7525, May
              2015, <http://www.rfc-editor.org/info/rfc7525>.

   [RFC8051]  Zhang, X., Ed. and I. Minei, Ed., "Applicability of a
              Stateful Path Computation Element (PCE)", RFC 8051,
              DOI 10.17487/RFC8051, January 2017,
              <http://www.rfc-editor.org/info/rfc8051>.

   [I-D.ietf-pce-pceps]
              Lopez, D., Dios, O., Wu, Q., and D. Dhody, "Secure
              Transport for PCEP", draft-ietf-pce-pceps-14 (work in
              progress), May 2017.

   [I-D.ietf-pce-pcep-yang]
              Dhody, D., Hardwick, J., Beeram, V., and j.
              jefftant@gmail.com, "A YANG Data Model for Path
              Computation Element Communications Protocol (PCEP)",
              draft-ietf-pce-pcep-yang-03 (work in progress), June 2017.

   [I-D.ietf-pce-association-diversity]
              Litkowski, S., Sivabalan, S., Barth, C., and D. Dhody,
              "Path Computation Element communication Protocol extension
              for signaling LSP diversity constraint", draft-ietf-pce-
              association-diversity-01 (work in progress), March 2017.

Authors' Addresses

   Hariharan Ananthakrishnan
   Packet Design
   1 South Almaden Blvd, #1150,
   San Jose, CA, 95113
   USA

   EMail: hari@packetdesign.com








Ananthakrishnan, et al. Expires December 31, 2017              [Page 12]


Internet-Draft      Stateful PCE LSP Path Protection           June 2017


   Siva Sivabalan
   Cisco
   2000 Innovation Drive
   Kananta, Ontaria K2K 3E8
   Cananda

   EMail: msiva@cisco.com


   Colby Barth
   Juniper Networks
   1194 N Mathilda Ave,
   Sunnyvale, CA, 94086
   USA

   EMail: cbarth@juniper.net


   Raveendra Torvi
   Juniper Networks
   1194 N Mathilda Ave,
   Sunnyvale, CA, 94086
   USA

   EMail: rtorvi@juniper.net


   Ina Minei
   Google, Inc
   1600 Amphitheatre Parkway
   Mountain View, CA, 94043
   USA

   EMail: inaminei@google.com


   Edward Crabbe
   Individual Contributor

   EMail: edward.crabbe@gmail.com











Ananthakrishnan, et al. Expires December 31, 2017              [Page 13]


Internet-Draft      Stateful PCE LSP Path Protection           June 2017


   Dhruv Dhody
   Huawei Technologies
   Divyashree Techno Park, Whitefield
   Bangalore, Karnataka  560066
   India

   EMail: dhruv.ietf@gmail.com












































Ananthakrishnan, et al. Expires December 31, 2017              [Page 14]


Html markup produced by rfcmarkup 1.129d, available from https://tools.ietf.org/tools/rfcmarkup/