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Versions: (draft-leedhody-pce-vn-association) 00 01 02 03

PCE Working Group                                                 Y. Lee
Internet-Draft                                                   Samsung
Intended status: Standards Track                                H. Zheng
Expires: April 22, 2021                              Huawei Technologies
                                                           D. Ceccarelli
                                                                Ericsson
                                                        October 19, 2020


 Path Computation Element communication Protocol (PCEP) extensions for
  Establishing Relationships between sets of LSPs and Virtual Networks
                    draft-ietf-pce-vn-association-03

Abstract

   This document describes how to extend Path Computation Element (PCE)
   Communication Protocol (PCEP) association mechanism introduced by the
   PCEP Association Group specification, to further associate sets of
   LSPs with a higher-level structure such as a virtual network (VN)
   requested by clients or applications.  This extended association
   mechanism can be used to facilitate virtual network control using PCE
   architecture.

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 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 April 22, 2021.

Copyright Notice

   Copyright (c) 2020 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



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   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.  Requirement Language  . . . . . . . . . . . . . . . . . .   3
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   4
   3.  Operation Overview  . . . . . . . . . . . . . . . . . . . . .   4
   4.  Extensions to PCEP  . . . . . . . . . . . . . . . . . . . . .   6
   5.  Applicability to H-PCE architecture . . . . . . . . . . . . .   7
   6.  Implementation Status . . . . . . . . . . . . . . . . . . . .   8
     6.1.  Huawei's Proof of Concept based on ONOS . . . . . . . . .   9
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .   9
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   9
     8.1.  Association Object Type Indicator . . . . . . . . . . . .   9
     8.2.  PCEP TLV Type Indicator . . . . . . . . . . . . . . . . .   9
     8.3.  PCEP Error  . . . . . . . . . . . . . . . . . . . . . . .  10
   9.  Manageability Considerations  . . . . . . . . . . . . . . . .  10
     9.1.  Control of Function and Policy  . . . . . . . . . . . . .  10
     9.2.  Information and Data Models . . . . . . . . . . . . . . .  10
     9.3.  Liveness Detection and Monitoring . . . . . . . . . . . .  10
     9.4.  Verify Correct Operations . . . . . . . . . . . . . . . .  10
     9.5.  Requirements On Other Protocols . . . . . . . . . . . . .  11
     9.6.  Impact On Network Operations  . . . . . . . . . . . . . .  11
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .  11
     10.1.  Normative References . . . . . . . . . . . . . . . . . .  11
     10.2.  Informative References . . . . . . . . . . . . . . . . .  12
   Appendix A.  Contributors . . . . . . . . . . . . . . . . . . . .  13
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  13

1.  Introduction

   The Path Computation Element communication Protocol (PCEP) provides
   mechanisms for Path Computation Elements (PCEs) to perform path
   computations in response to Path Computation Clients' (PCCs)
   requests.

   [RFC8051] describes general considerations for a stateful PCE
   deployment and examines its applicability and benefits, as well as
   its challenges and limitations through a number of use cases.
   [RFC8231] describes a set of extensions to PCEP to provide stateful
   control.  A stateful PCE has access to not only the information
   carried by the network's Interior Gateway Protocol (IGP), but also



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   the set of active paths and their reserved resources for its
   computations.  The additional state allows the PCE to compute
   constrained paths while considering individual LSPs and their
   interactions.

   [RFC8281] describes the setup, maintenance and teardown of PCE-
   initiated LSPs under the stateful PCE model.

   [RFC8697] introduces a generic mechanism to create a grouping of
   LSPs.  This grouping can then be used to define association between
   sets of LSPs or between a set of LSPs and a set of attributes.

   [RFC8453] describes various Virtual Network (VN) operations initiated
   by a customer/application.  In this context, there is a need for
   associating a set of LSPs with a VN "construct" to facilitate VN
   operations in PCE architecture.  This association allows the PCEs to
   identify which LSPs belong to a certain VN.  The PCE could then use
   this association to optimize all LSPs belonging to the VN together.
   The PCE could further take VN specific actions on the LSPs such as
   relaxation of constraints, policy actions, setting default behavior
   etc.

   [RFC8637] examines the PCE and ACTN architecture and describes how
   the PCE architecture is applicable to ACTN.  [RFC6805] and [RFC8751]
   describes a hierarchy of stateful PCEs with Parent PCE coordinating
   multi-domain path computation function between Child PCE(s) and thus
   making it the base for PCE applicability for ACTN.  In this text
   child PCE would be same as Provisioning Network Controller (PNC), and
   the parent PCE as Multi-domain Service Coordinator (MDSC) [RFC8453].

   This document specifies a PCEP extension to associate a set of LSPs
   based on Virtual Network (VN) (or customer).  A Virtual Network (VN)
   is a customer view of the TE network.  Depending on the agreement
   between client and provider various VN operations and VN views are
   possible as described in [RFC8453].

1.1.  Requirement Language

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








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2.  Terminology

   The terminology is as per [RFC4655], [RFC5440], [RFC6805], [RFC8231]
   and [RFC8453].

3.  Operation Overview

   As per [RFC8697], LSPs are associated with other LSPs with which they
   interact by adding them to a common association group.

   An association group based on VN is useful for various optimizations
   that should be applied by considering all the LSPs in the
   association.  This includes, but not limited to -

   o  Path Computation: When computing path for a LSP, the impact of
      this LSP, on the other LSPs belonging to the same VN is useful to
      analyze.  The aim would be optimize overall VN and all LSPs,
      rather than a single LSP.  Also, the optimization criteria such as
      minimize the load of the most loaded link (MLL) [RFC5541] and
      other could be applied for all the LSP belonging to the same VN,
      identified by the VN association.

   o  Path Re-Optimization: The child PCE or the parent PCE would like
      to use advanced path computation algorithm and optimization
      technique that consider all the LSPs belonging to a VN/customer
      and optimize them all together during the re-optimization.

   This association is useful in PCEP session between parent PCE (MDSC)
   and child PCE (PNC).  When computing the path, the child PCE (PNC)
   refer to the VN association in the request from the parent PCE (MDSC)
   and maps the VN to the associated LSPs and the network resources.
   Based on this information, operator policy and various constraints,
   the path is computed and replied to the parent PCE (MDSC).  The VN
   association information could be included as a part of response as
   well.  The figure describes a typical VN operations using PCEP for
   illustration purpose.  It is worth noting that in a multi-domain
   scenario, the different domain is controlled by different child PCEs.
   In order to set up the end-to-end tunnel, multiple segments need to
   be stitched, by the border nodes in each domain who receives the
   instruction from their child PCE (PNC).











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                                    ******
                          ..........*MDSC*..............................
                       .            ****** ..                   MPI    .
                    .                .        .                 PCEP   .
                 .                   .          .   PCInitiate LSPx   .
               .                    .             .   with VNAG = 10   .
              .                    .                .                  .
             .                    .                  .                 .
            .                    .                    .                .
            v                    v                    v                .
          ******               ******               ******             .
          *PNC1*               *PNC2*               *PNC4*             .
          ******               ******               ******             .
          +---------------+    +---------------+    +---------------+  .
          |A              |----|               |----|              C|  .
          |               |    |               |    |               |  .
          |DOMAIN 1       |----|DOMAIN 2       |----|DOMAIN 4       |  .
          +------------B13+    +---------------+    +B43------------+  .
                                                   /                  .
                              ******              /                   .
                              *PNC3*<............/.....................
                              ******            /
                              +---------------+/
                               B31           B34
                              |               |
                              |DOMAIN 3      B|
                              +---------------+

          MDSC -> Parent PCE
          PNC  -> Child  PCE
          MPI  -> PCEP

   In this draft, this grouping is used to define associations between a
   set of LSPs and a virtual network, a new association group is defined
   below -

   o  VN Association Group (VNAG)

   One new Association type is defined as described in the Association
   object -

   o  Association type = TBD1 ("VN Association") for VNAG

   The scope and handling of VNAG identifier is similar to the generic
   association identifier defined in [RFC8697] .

   In this document VNAG object refers to an Association Object with the
   Association type set to "VNAG".



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   Local polices on the PCE MAY define the computational and
   optimization behavior for the LSPs in the VN.  An LSP MUST NOT belong
   to more than one VNAG.  If an implementation encounters more than one
   VNAG, it MUST consider the first occurrence and ignore the others.

   [RFC8697] specify the mechanism for the capability advertisement of
   the association types supported by a PCEP speaker by defining a
   ASSOC-Type-List TLV to be carried within an OPEN object.  This
   capability exchange for the association type described in this
   document (i.e.  VN Association Type) MUST be done before using the
   policy association.  Thus the PCEP speaker MUST include the VN
   Association Type (TBD1) in the ASSOC-Type-List TLV before using the
   VNAG in the PCEP messages.

   This Association-Type is dynamic in nature and created by the Parent
   PCE (MDSC) for the LSPs belonging to the same VN or customer.  These
   associations are conveyed via PCEP messages to the PCEP peer.
   Operator-configured Association Range MUST NOT be set for this
   association-type and MUST be ignored.

4.  Extensions to PCEP

   The format of VNAG is as per the ASSOCIATION object [RFC8697].

   This document defines one mandatory TLV "VIRTUAL-NETWORK-TLV" and one
   new optional TLV "VENDOR-INFORMATION-TLV"; apart from this TLV,
   VENDOR-INFORMATION-TLV can be used to carry arbitrary vendor specific
   information.

   o  VIRTUAL-NETWORK-TLV: Used to communicate the VN Identifier.

   o  VENDOR-INFORMATION-TLV: Used to communicate arbitrary vendor
      specific behavioral information, described in [RFC7470].

   The format of VIRTUAL-NETWORK-TLV 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 (variable)       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      //                   Virtual Network Name                      //
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
                 Figure 1: The VIRTUAL-NETWORK-TLV formats

   Type: TBD2 (to be allocated by IANA)



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   Length: Variable Length

   Virtual Network Name (variable): an unique symbolic name for the VN.
   It SHOULD be a string of printable ASCII characters, without a NULL
   terminator.  The VN name is a human-readable string that identifies a
   VN and can be specified with the association information.  An
   implementation could use the VN name to maintain a mapping to the VN
   association group and the LSPs associated with the VN.  The VN name
   MAY be specified by an operator or auto-generated by the PCEP
   speaker.

   The VIRTUAL-NETWORK-TLV MUST be included in VNAG object.If a PCEP
   speaker receives the VNAG object without the VIRTUAL-NETWORK-TLV, it
   MUST send a PCErr message with Error-Type=6 (mandatory object
   missing) and Error-Value=TBD3 (VIRTUAL-NETWORK-TLV missing) and close
   the session.

   The format of VENDOR-INFORMATION-TLV is defined in [RFC7470].

5.  Applicability to H-PCE architecture

   The ability to compute shortest constrained TE LSPs in Multiprotocol
   Label Switching (MPLS) and Generalized MPLS (GMPLS) networks across
   multiple domains has been identified as a key motivation for PCE
   development.  [RFC6805] describes a Hierarchical PCE (H-PCE)
   architecture which can be used for computing end-to-end paths for
   inter-domain MPLS Traffic Engineering (TE) and GMPLS Label Switched
   Paths (LSPs).  Within the hierarchical PCE architecture, the parent
   PCE is used to compute a multi-domain path based on the domain
   connectivity information.  A child PCE may be responsible for a
   single domain or multiple domains, it is used to compute the intra-
   domain path based on its domain topology information.

   [RFC8751] introduces general considerations for stateful PCE(s) in
   hierarchical PCE architecture.  In particular, the behavior changes
   and additions to the existing stateful PCE mechanisms in the context
   of a H-PCE architecture.

   In Stateful H-PCE architecture, the Parent PCE receives a virtual
   network creation request by its client over its Northbound API.  This
   VN is uniquely identified by an Association ID in VNAG as well as the
   VIRTUAL-NETWORK name.  This VN may comprise multiple LSPs in the
   network in a single domain or across multiple domains.

   As the Parent PCE computes the optimum E2E paths for each tunnel in
   VN, it MUST associate each LSP with the VN to which it belongs.
   Parent PCE sends a PCInitiate Message with this association
   information in the VNAG Object (See Section 4 for details).  This in



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   effect binds an LSP that is to be instantiated at the child PCE with
   the VN.

   Whenever changes occur with the instantiated LSP in a domain network,
   the domain child PCE reports the changes using a PCRpt Message in
   which the VNAG Object indicates the relationship between the LSP and
   the VN.

   Whenever an update occurs with VNs in the Parent PCE (via the
   client's request), the parent PCE sends an PCUpd Message to inform
   each affected child PCE of this change.

   The Child PCE could then use this association to optimize all LSPs
   belonging to the same VN association together.  The Child PCE could
   further take VN specific actions on the LSPs such as relaxation of
   constraints, policy actions, setting default behavior etc.  The
   parent PCE could also maintain all E2E LSP or per-domain path
   segments under a single VN association.

6.  Implementation Status

   [Note to the RFC Editor - remove this section before publication, as
   well as remove the reference to RFC 7942.]

   This section records the status of known implementations of the
   protocol defined by this specification at the time of posting of this
   Internet-Draft, and is based on a proposal described in [RFC7942].
   The description of implementations in this section is intended to
   assist the IETF in its decision processes in progressing drafts to
   RFCs.  Please note that the listing of any individual implementation
   here does not imply endorsement by the IETF.  Furthermore, no effort
   has been spent to verify the information presented here that was
   supplied by IETF contributors.  This is not intended as, and must not
   be construed to be, a catalog of available implementations or their
   features.  Readers are advised to note that other implementations may
   exist.

   According to [RFC7942], "this will allow reviewers and working groups
   to assign due consideration to documents that have the benefit of
   running code, which may serve as evidence of valuable experimentation
   and feedback that have made the implemented protocols more mature.
   It is up to the individual working groups to use this information as
   they see fit".








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6.1.  Huawei's Proof of Concept based on ONOS

   The PCE function was developed in the ONOS open source platform.
   This extension was implemented on a private version as a proof of
   concept to ACTN.

   o  Organization: Huawei

   o  Implementation: Huawei's PoC based on ONOS

   o  Description: PCEP as a southbound plugin was added to ONOS.  To
      support ACTN, this extension in PCEP is used.  Refer
      https://wiki.onosproject.org/display/ONOS/PCEP+Protocol

   o  Maturity Level: Prototype

   o  Coverage: Full

   o  Contact: satishk@huawei.com

7.  Security Considerations

   This document defines one new type for association, which do not add
   any new security concerns beyond those discussed in [RFC5440],
   [RFC8231] and [RFC8697] in itself.

   Some deployments may find the Virtual Network Name and the VN
   associations as extra sensitive; and thus should employ suitable PCEP
   security mechanisms like TCP-AO [RFC5925] or [RFC8253].

8.  IANA Considerations

8.1.  Association Object Type Indicator

   This document defines a new association type, originally defined in
   [RFC8697], 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 [RFC8697]), as follows:

         Value     Name                        Reference

         TBD1      VN Association Type         [This I.D.]

8.2.  PCEP TLV Type Indicator

   This document defines a new TLV for carrying additional information
   of LSPs within a path protection association group.  IANA is




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   requested to make the assignment of a new value for the existing
   "PCEP TLV Type Indicators" registry as follows:

         Value     Name                        Reference

         TBD2      VIRTUAL-NETWORK-TLV         [This I.D.]

8.3.  PCEP Error

   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

         6           Mandatory Object missing
                     Error-value=TBD3: VIRTUAL-NETWORK TLV missing [This
         I.D.]

9.  Manageability Considerations

9.1.  Control of Function and Policy

   An operator MUST BE allowed to mark LSPs that belong to the same VN.
   This could also be done automatically based on the VN configuration.

9.2.  Information and Data Models

   The PCEP YANG module [I-D.ietf-pce-pcep-yang] should support the
   association between LSPs including VN association.

9.3.  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].

9.4.  Verify Correct Operations

   Mechanisms defined in this document do not imply any new operation
   verification requirements in addition to those already listed in
   [RFC5440].








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9.5.  Requirements On Other Protocols

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

9.6.  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].

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,
              <https://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,
              <https://www.rfc-editor.org/info/rfc5440>.

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

   [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,
              <https://www.rfc-editor.org/info/rfc8231>.

   [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,
              <https://www.rfc-editor.org/info/rfc8281>.

   [RFC8697]  Minei, I., Crabbe, E., Sivabalan, S., Ananthakrishnan, H.,
              Dhody, D., and Y. Tanaka, "Path Computation Element
              Communication Protocol (PCEP) Extensions for Establishing
              Relationships between Sets of Label Switched Paths
              (LSPs)", RFC 8697, DOI 10.17487/RFC8697, January 2020,
              <https://www.rfc-editor.org/info/rfc8697>.





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10.2.  Informative References

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

   [RFC5925]  Touch, J., Mankin, A., and R. Bonica, "The TCP
              Authentication Option", RFC 5925, DOI 10.17487/RFC5925,
              June 2010, <https://www.rfc-editor.org/info/rfc5925>.

   [RFC6805]  King, D., Ed. and A. Farrel, Ed., "The Application of the
              Path Computation Element Architecture to the Determination
              of a Sequence of Domains in MPLS and GMPLS", RFC 6805,
              DOI 10.17487/RFC6805, November 2012,
              <https://www.rfc-editor.org/info/rfc6805>.

   [RFC7942]  Sheffer, Y. and A. Farrel, "Improving Awareness of Running
              Code: The Implementation Status Section", BCP 205,
              RFC 7942, DOI 10.17487/RFC7942, July 2016,
              <https://www.rfc-editor.org/info/rfc7942>.

   [RFC8453]  Ceccarelli, D., Ed. and Y. Lee, Ed., "Framework for
              Abstraction and Control of TE Networks (ACTN)", RFC 8453,
              DOI 10.17487/RFC8453, August 2018,
              <https://www.rfc-editor.org/info/rfc8453>.

   [RFC8637]  Dhody, D., Lee, Y., and D. Ceccarelli, "Applicability of
              the Path Computation Element (PCE) to the Abstraction and
              Control of TE Networks (ACTN)", RFC 8637,
              DOI 10.17487/RFC8637, July 2019,
              <https://www.rfc-editor.org/info/rfc8637>.

   [RFC5541]  Le Roux, JL., Vasseur, JP., and Y. Lee, "Encoding of
              Objective Functions in the Path Computation Element
              Communication Protocol (PCEP)", RFC 5541,
              DOI 10.17487/RFC5541, June 2009,
              <https://www.rfc-editor.org/info/rfc5541>.

   [RFC7470]  Zhang, F. and A. Farrel, "Conveying Vendor-Specific
              Constraints in the Path Computation Element Communication
              Protocol", RFC 7470, DOI 10.17487/RFC7470, March 2015,
              <https://www.rfc-editor.org/info/rfc7470>.

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



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   [RFC8253]  Lopez, D., Gonzalez de Dios, O., Wu, Q., and D. Dhody,
              "PCEPS: Usage of TLS to Provide a Secure Transport for the
              Path Computation Element Communication Protocol (PCEP)",
              RFC 8253, DOI 10.17487/RFC8253, October 2017,
              <https://www.rfc-editor.org/info/rfc8253>.

   [RFC8751]  Dhody, D., Lee, Y., Ceccarelli, D., Shin, J., and D. King,
              "Hierarchical Stateful Path Computation Element (PCE)",
              RFC 8751, DOI 10.17487/RFC8751, March 2020,
              <https://www.rfc-editor.org/info/rfc8751>.

   [I-D.ietf-pce-pcep-yang]
              Dhody, D., Hardwick, J., Beeram, V., and J. Tantsura, "A
              YANG Data Model for Path Computation Element
              Communications Protocol (PCEP)", draft-ietf-pce-pcep-
              yang-14 (work in progress), July 2020.

Appendix A.  Contributors

      Dhruv Dhody
      Huawei Technologies
      Divyashree Technopark, Whitefield
      Bangalore, Karnataka  560066
      India

      Email: dhruv.ietf@gmail.com

      Qin Wu
      Huawei Technologies
      China

      Email: bill.wu@huawei.com

      Xian Zhang
      Huawei Technologies
      China

      Email: zhang.xian@huawei.com

Authors' Addresses

   Young Lee
   Samsung
   Seoul
   South Korea

   Email: younglee.tx@gmail.com




Lee, et al.              Expires April 22, 2021                [Page 13]


Internet-Draft             PCE VN Association               October 2020


   Haomian Zheng
   Huawei Technologies
   H1, Huawei Xiliu Beipo Village, Songshan Lake
   Dongguan, Guangdong  523808
   China

   Email: zhenghaomian@huawei.com


   Daniele Ceccarelli
   Ericsson
   Torshamnsgatan,48
   Stockholm
   Sweden

   Email: daniele.ceccarelli@ericsson.com



































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