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Path Computation Element Communication Protocol (PCEP) Extensions for Native IP Networks
draft-ietf-pce-pcep-extension-native-ip-39

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This is an older version of an Internet-Draft whose latest revision state is "Active".
Authors Aijun Wang , Boris Khasanov , Sheng Fang , Ren Tan , Chun Zhu
Last updated 2024-09-10 (Latest revision 2024-09-01)
Replaces draft-wang-pce-pcep-extension-native-ip
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Nov 2023
Submit PCEP Native-IP extensions as a Proposed Standard
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draft-ietf-pce-pcep-extension-native-ip-39
PCE Working Group                                                A. Wang
Internet-Draft                                             China Telecom
Intended status: Experimental                                B. Khasanov
Expires: 6 March 2025                             MTS Web Services (MWS)
                                                                 S. Fang
                                                                  R. Tan
                                                     Huawei Technologies
                                                                  C. Zhu
                                                         ZTE Corporation
                                                        2 September 2024

 Path Computation Element Communication Protocol (PCEP) Extensions for
                           Native IP Networks
               draft-ietf-pce-pcep-extension-native-ip-39

Abstract

   This document introduces extensions to the PCE Communication Protocol
   (PCEP) to support path computation in native IP networks through a
   PCE-based central control mechanism known as Centralized Control
   Dynamic Routing (CCDR).  These extensions empower a PCE to calculate
   and manage paths specifically for native IP networks, expand PCEP’s
   capabilities beyond its traditional use in MPLS and GMPLS networks.
   By implementing these extensions, IP network resources can be
   utilized more efficiently, facilitating the deployment of traffic
   engineering in native IP environments.

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 6 March 2025.

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Copyright Notice

   Copyright (c) 2024 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 Revised BSD License text as
   described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Revised BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Conventions used in this document . . . . . . . . . . . . . .   3
     2.1.  Use of RBNF . . . . . . . . . . . . . . . . . . . . . . .   4
     2.2.  Experimental Status Consideration . . . . . . . . . . . .   4
   3.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   4
   4.  Capability Advertisement  . . . . . . . . . . . . . . . . . .   5
     4.1.  Open Message  . . . . . . . . . . . . . . . . . . . . . .   5
   5.  PCEP Messages . . . . . . . . . . . . . . . . . . . . . . . .   6
     5.1.  The PCInitiate Message  . . . . . . . . . . . . . . . . .   6
     5.2.  The PCRpt Message . . . . . . . . . . . . . . . . . . . .   8
   6.  PCECC Native IP TE Procedures . . . . . . . . . . . . . . . .   9
     6.1.  BGP Session Establishment Procedures  . . . . . . . . . .   9
     6.2.  Explicit Route Establishment Procedures . . . . . . . . .  12
     6.3.  BGP Prefix Advertisement Procedures . . . . . . . . . . .  15
     6.4.  Selection of Raw Mode and Tunnel Mode Forwarding
           Strategy  . . . . . . . . . . . . . . . . . . . . . . . .  17
     6.5.  Clean Up  . . . . . . . . . . . . . . . . . . . . . . . .  17
     6.6.  Other Procedures  . . . . . . . . . . . . . . . . . . . .  18
   7.  New PCEP Objects  . . . . . . . . . . . . . . . . . . . . . .  18
     7.1.  CCI Object  . . . . . . . . . . . . . . . . . . . . . . .  18
     7.2.  BGP Peer Info Object  . . . . . . . . . . . . . . . . . .  19
     7.3.  Explicit Peer Route Object  . . . . . . . . . . . . . . .  21
     7.4.  Peer Prefix Advertisement Object  . . . . . . . . . . . .  23
   8.  New Error-Types and Error-Values Defined  . . . . . . . . . .  26
   9.  BGP Considerations  . . . . . . . . . . . . . . . . . . . . .  28
   10. Deployment Considerations . . . . . . . . . . . . . . . . . .  28
   11. Manageability Considerations  . . . . . . . . . . . . . . . .  29
     11.1.  Control of Function and Policy . . . . . . . . . . . . .  29
     11.2.  Information and Data Models  . . . . . . . . . . . . . .  29
     11.3.  Liveness Detection and Monitoring  . . . . . . . . . . .  29
     11.4.  Verify Correct Operations  . . . . . . . . . . . . . . .  29
     11.5.  Requirements on Other Protocols  . . . . . . . . . . . .  30

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     11.6.  Impact on Network Operations . . . . . . . . . . . . . .  30
   12. Security Considerations . . . . . . . . . . . . . . . . . . .  30
   13. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  30
     13.1.  Path Setup Type Registry . . . . . . . . . . . . . . . .  30
     13.2.  PCECC-CAPABILITY sub-TLV's Flag field  . . . . . . . . .  31
     13.3.  PCEP Object  . . . . . . . . . . . . . . . . . . . . . .  31
     13.4.  PCEP-Error Object  . . . . . . . . . . . . . . . . . . .  32
     13.5.  CCI Object Flag Field  . . . . . . . . . . . . . . . . .  32
     13.6.  BPI Object Status Code . . . . . . . . . . . . . . . . .  33
     13.7.  BPI Object Error Code  . . . . . . . . . . . . . . . . .  33
     13.8.  BPI Object Flag Field  . . . . . . . . . . . . . . . . .  33
   14. Contributor . . . . . . . . . . . . . . . . . . . . . . . . .  34
   15. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . .  34
   16. References  . . . . . . . . . . . . . . . . . . . . . . . . .  34
     16.1.  Normative References . . . . . . . . . . . . . . . . . .  34
     16.2.  Informative References . . . . . . . . . . . . . . . . .  36
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  37

1.  Introduction

   Generally, Multiprotocol Label Switching Traffic Engineering (MPLS-
   TE) requires the corresponding network devices to support Resource
   ReSerVation Protocol (RSVP)[RFC3209]/Label Distribution Protocol
   (LDP)[RFC5036] protocols to ensure the End-to-End (E2E) traffic
   performance.  But in native IP network scenarios described in
   [RFC8735], there will be no such signaling protocol to synchronize
   the actions among different network devices.  It is feasible to use
   the central control mode described in [RFC8283] to correlate the
   forwarding behavior among different network devices.  [RFC8821]
   describes the architecture and solution philosophy for the E2E
   traffic assurance in the Native IP network via multiple Border
   Gateway Protocol (BGP) sessions-based solution.  It requires only the
   PCE to send the instructions to the PCCs, to build multiple BGP
   sessions, distribute different prefixes on the established BGP
   sessions and assign the different paths to the BGP next hops.

   This document describes the corresponding Path Computation Element
   Communication Protocol (PCEP) extensions to transfer the key
   information about BGP peer, peer prefix advertisement, and the
   explicit peer route on on-path routers.

2.  Conventions used in this document

   The keywords "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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2.1.  Use of RBNF

   The message formats in this document are illustrated using Routing
   Backus-Naur Form (RBNF) encoding, as specified in [RFC5511].  The use
   of RBNF is illustrative only and may elide certain important details;
   the normative specification of messages is found in the prose
   description.  If there is any divergence between the RBNF and the
   prose, the prose is considered authoritative.

2.2.  Experimental Status Consideration

   The procedures outlined in this document are experimental.  The
   experiment aims to explore the use of PCE (and PCEP) for end-to-end
   traffic assurance in Native IP networks through multiple BGP
   sessions.  Additional implementation is necessary to gain a deeper
   understanding of the operational impact, scalability, and stability
   of the mechanism described.  Feedback from deployments will be
   crucial in determining whether this specification should advance from
   Experimental to the IETF Standards Track.

3.  Terminology

   This document uses the following terms defined in [RFC5440]: PCC,
   PCE, PCEP.

   The following terminology is used in this document:

   *  BPI: BGP Peer Info

   *  CCDR: Central Control Dynamic Routing

   *  CCI: Central Controller Instructions, defined in [RFC9050]

   *  E2E: End-to-End

   *  EPR: Explicit Peer Route

   *  Native IP network: Network that forwards traffic based solely on
      the IP address, instead of other indicator, for example MPLS etc.

   *  PCECC: PCE as a Central Controller, defined in [RFC8283]

   *  PPA: Peer Prefix Advertisement

   *  PST: Path Setup Type, defined in [RFC8408]

   *  SRP: Stateful PCE Request Parameters, defined in [RFC8231]

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   *  RR: Route Reflector

4.  Capability Advertisement

4.1.  Open Message

   During the PCEP Initialization Phase, PCEP Speakers (PCE or PCC)
   advertise their support of Native IP extensions.

   This document defines a new Path Setup Type (PST) [RFC8408] for
   Native-IP, as follows:

   *  PST = 4: Path is a Native IP TE path as per [RFC8821].

   A PCEP speaker MUST indicate its support of the function described in
   this document by sending a PATH-SETUP-TYPE-CAPABILITY TLV in the OPEN
   object with this new PST included in the PST list.

   [RFC9050] defined the PCECC-CAPABILITY sub-TLV to exchange
   information about their PCECC capability.  A new flag is defined in
   PCECC-CAPABILITY sub-TLV for Native IP:

   N (NATIVE-IP-TE-CAPABILITY - 1 bit - 30): When set to 1 by a PCEP
   speaker, this flag indicates that the PCEP speaker is capable of TE
   in a Native IP network, as specified in this document.  Both the PCC
   and PCE MUST set this flag to support this extension.

   If a PCEP speaker receives the PATH-SETUP-TYPE-CAPABILITY TLV with
   the newly defined path setup type, but without the N bit set in
   PCECC-CAPABILITY sub-TLV, it MUST:

   *  send a PCErr message with Error-Type=10 (Reception of an invalid
      object) and Error-Value=39 (PCECC NATIVE-IP-TE-CAPABILITY bit is
      not set).

   *  terminate the PCEP session

   If a PCEP speaker receives the PATH-SETUP-TYPE-CAPABILITY TLV with
   the newly defined path setup type, but without the PCECC-CAPABILITY
   sub-TLV, it MUST:

   *  send a PCErr message with Error-Type=10(Reception of an invalid
      object) and Error-Value=33 (Missing PCECC Capability sub-TLV).

   *  terminate the PCEP session

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   If one or both speakers (PCE and PCC) have not indicated the support
   for Native-IP, the PCEP extensions for the Native-IP MUST NOT be
   used.  If a Native-IP operation is attempted when both speakers have
   not agreed on the OPEN messages, the receiver of the message MUST:

   *  send a PCErr message with Error-Type=19 (Invalid Operation) and
      Error-value=TBD1 (Attempted Native-IP operations when the
      capability was not advertised) and

   *  terminate the PCEP session.

5.  PCEP Messages

   PCECC Native IP TE solution uses the existing PCE Label Switched Path
   (LSP) Initiate Request message (PCInitiate) [RFC8281], and PCE Report
   message (PCRpt) [RFC8231] to accomplish the multiple BGP sessions
   establishment, E2E Native-IP TE path deployment, and route prefixes
   advertisement among different BGP sessions.  A new PST for Native-IP
   is used to indicate the path setup based on TE in Native IP networks.

   The extended PCInitiate message described in [RFC9050] is used to
   download or remove the central controller's instructions (CCIs).
   [RFC9050] specifies an object called CCI for the encoding of the
   central controller's instructions.  This document specifies a new CCI
   Object-Type for Native IP.  The PCEP messages are extended in this
   document to handle the PCECC operations for Native IP.  Three new
   PCEP Objects (BGP Peer Info (BPI) Object, Explicit Peer Route (EPR)
   Object, and Peer Prefix Advertisement (PPA) Object) are defined in
   this document.  Refer to Section 7 for detailed object definitions.
   All PCEP procedures specified in [RFC9050] continue to apply unless
   specified otherwise.

5.1.  The PCInitiate Message

   The PCInitiate Message defined in [RFC8281] and extended in [RFC9050]
   is further extended to support Native-IP CCI.

   The format of the extended PCInitiate message is as follows:

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        <PCInitiate Message> ::= <Common Header>
                                 <PCE-initiated-lsp-list>
     Where:
        <Common Header> is defined in [RFC5440]

        <PCE-initiated-lsp-list> ::= <PCE-initiated-lsp-request>
                                     [<PCE-initiated-lsp-list>]

        <PCE-initiated-lsp-request> ::=
                             (<PCE-initiated-lsp-instantiation>|
                              <PCE-initiated-lsp-deletion>|
                              <PCE-initiated-lsp-central-control>)

        <PCE-initiated-lsp-central-control> ::= <SRP>
                                                <LSP>
                                                <cci-list>

        <cci-list> ::=  <CCI>
                        [<BPI>|<EPR>|<PPA>]
                        [<cci-list>]

   Where:

      <PCE-initiated-lsp-instantiation> and <PCE-initiated-lsp-deletion>
      are as per [RFC8281].

      The LSP and SRP objects are defined in [RFC8231].

   When the PCInitiate message is used for Native IP instructions, i.e.
   When the CCI Object-Type is 2, the SRP, LSP and CCI objects MUST be
   present.  Error handling for missing SRP, LSP or CCI objects MUST be
   performed as specified in [RFC9050].  Additionally, exactly one
   object among the BPI, EPR, or PPA objects MUST be present.  The PLSP-
   ID and Symbolic Path Name TLVs are set as per the existing rules in
   [RFC8231], [RFC8281], and [RFC9050].  The Symbolic Path Name is used
   by the PCE/PCC to uniquely identify the E2E native IP TE path.  The
   related Native-IP instructions with BPI, EPR or PPA objects are
   identified by the same Symbolic Path Name.

   If none of the BPI, EPR or PPA objects are present, the receiving PCC
   MUST send a PCErr message with Error-type=6 (Mandatory Object
   missing) and Error-value=19 (Native IP object missing).  If there is
   more than one instance of BPI, EPR or PPA object present, the
   receiving PCC MUST send a PCErr message with Error-type=19 (Invalid
   Operation) and Error-value=22 (Only one BPI, EPR or PPA object can be
   included in this message).

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   When the PCInitiate message is not used for Native IP instructions,
   i.e. When CCI Object-Type is not equal to 2, the BPI, EPR and PPA
   objects SHOULD NOT be present.  If present, they MUST be ignored by
   the receiver.

   To clean up the existing Native IP instructions, the SRP object MUST
   set the R (remove) bit.

5.2.  The PCRpt Message

   The PCRpt message is used to acknowledge the Native-IP instructions
   received from the central controller (PCE) as well as during the
   State Synchronization phase.

   The format of the PCRpt message is as follows:

         <PCRpt Message> ::= <Common Header>
                             <state-report-list>
      Where:

         <state-report-list> ::= <state-report>[<state-report-list>]

         <state-report> ::= (<lsp-state-report>|
                             <central-control-report>)

         <lsp-state-report> ::= [<SRP>]
                                <LSP>
                                <path>

         <central-control-report> ::= [<SRP>]
                                      <LSP>
                                      <cci-list>

         <cci-list> ::=  <CCI>
                        [<BPI>|<EPR>|<PPA>]
                        [<cci-list>]

      Where: <path> is as per [RFC8231] and the LSP and SRP objects are
      also defined in [RFC8231].

   The error handling for missing CCI objects is as per [RFC9050].
   Furthermore, one, and only one, object among BPI, EPR or PPA object
   MUST be present.

   If none of the BPI, EPR or PPA objects are present, the receiving PCE
   MUST send a PCErr message with Error-type=6 (Mandatory Object
   missing) and Error-value=19 (Native IP object missing).  If there are
   more than one instance of BPI, EPR or PPA objects present, the

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   receiving PCE MUST send a PCErr message with Error-type=19 (Invalid
   Operation) and Error-value=22 (Only one BPI, EPR or PPA object can be
   included in this message).

   When the PCInitiate message is not used for Native IP instructions,
   i.e. When CCI Object-Type is not equal to 2, the BPI, EPR and PPA
   objects SHOULD NOT be present.  If present, they MUST be ignored by
   the receiver.

6.  PCECC Native IP TE Procedures

   The detailed procedures for the TE in the native IP environment are
   described in the following sections.

6.1.  BGP Session Establishment Procedures

   The PCInitiate and PCRpt message pair is used to exchange the
   configuration parameters for a BGP peer session.  This pair of PCEP
   messages are exchanged between a PCE and each BGP peer (acting as
   PCC) which needs to establish a BGP session.  After the BGP peer
   session has been initiated via this pair of PCEP messages, the BGP
   session establishes and operates in a normal fashion.  The BGP peers
   can be used for External BGP (EBGP) peers or Internal BGP (IBGP)
   peers.  For IBGP connection topologies, the Route Reflector (RR) is
   required.

   The PCInitiate message is sent to the BGP router and/or RR (which are
   acting as PCC).

   The RR topology for a single Autonomous System (AS) is shown in
   Figure 1.  The BGP routers R1, R3, and R7 are within a single AS.  R1
   and R7 are BGP RR clients, and R3 is a RR.  The PCInitiate message is
   sent to the BGP routers R1, R3 and R7 that need to establish a BGP
   session.

   PCInitiate message creates an auto-configuration function for these
   BGP peers by providing the indicated Peer AS and the Local/Peer IP
   Address.

   When the PCC receives the BPI and CCI object (with the R bit set to 0
   in the SRP object) in the PCInitiate message, the PCC SHOULD try to
   establish the BGP session with the indicated Peer as per AS and
   Local/Peer IP address.

   During the establishment procedure, the PCC MUST report to the PCE
   the status of the BGP session via the PCRpt message, with the status
   field in the BPI object set to the appropriate value and the
   corresponding SRP and CCI objects included.

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   When the PCC receives this message with the R bit set to 1 in the SRP
   object in the PCInitiate message, the PCC MUST clear the BGP
   configuration and tear down the BGP session that is indicated by the
   BPI object.

   When the PCC clears successfully the specified BGP session
   configuration, it MUST report the result via the PCRpt message, with
   the BPI object included, and the corresponding SRP and CCI objects.

                                +------------------+
                    +----------->       PCE        <----------+
                    |           +--------^---------+          |
                    |                    |                    |
                    |             PCInitiate/PCRpt            |
                    |                    |                    |
                    |               +----v--+                 |
                    +---------------+ R3(RR)+-----------------+
                    |               +-------+                 |
              PCInitiate/PCRpt                         PCInitiate/PCRpt
                    |                                         |
                   +v-+          +--+          +--+         +-v+
                   |R1+----------+R5+----------+R6+---------+R7|
                   ++-+          +-++          +--+         +-++
                    |              |                          |
                    |            +--+          +--+           |
                    +------------+R2+----------+R4+-----------+
                                 +--+          +--+
          Figure 1: BGP Session Establishment Procedures(R3 act as RR)

   The message peers, message type, message key parameters and
   procedures in the above figures are shown below:

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               +-------+                                       +-------+
               |PCC    |                                       |  PCE  |
               |R1     |                                       +-------+
        +------|       |                                            |
        | PCC  +-------+                                            |
        | R3     | |   (For R1/R3 BGP Session on R1)                |
 +------|        | |<-PCInitiate,CC-ID=X,Symbolic Path Name=Class A-|
 |      |        | |BPI Object(Peer AS, Local_IP=R1_A, Peer_IP=R3_A)|
 |PCC   +--------+ |                                                |
 |R7      |  |     |----PCRpt,CC-ID=X(Symbolic Path Name=Class A)-->|
 |        |  |     |BPI Object(Peer AS, Local_IP=R1_A, Peer_IP=R3_A)|
 +--------+  |                                                      |
     |       |          (For R1/R3 BGP Session on R3)               |
     |       |<--PCInitiate,CC-ID=Y1,Symbolic Path Name=Class A-----|
     |       |      BPI Object(Peer AS, Local_IP=R3_A, Peer_IP=R1_A)|
     |       |---PCRpt,CC-ID=Y1,Symbolic Path Name=Class A--------->|
     |       |      BPI Object(Peer AS, Local_IP=R3_A, Peer_IP=R1_A)|
     |       |                                                      |
     |       |          (For R3/R7 BGP Session on R3)               |
     |       |<--PCInitiate,CC-ID=Y2,Symbolic Path Name=Class A-----|
     |       |  BPI Object(Peer AS, Local_IP=R3_A, Peer_IP=R7_A)    |
     |       |----PCRpt,CC-ID=Y2,Symbolic Path Name=Class A-------->|
     |       |  BPI Object(Peer AS, Local_IP=R3_A, Peer_IP=R7_A)    |
     |                                                              |
     |                  (For R3/R7 BGP Session on R7)               |
     |<--PCInitiate,CC-ID=Z,Symbolic Path Name=Class A--------------|
     |            BPI Object(Peer AS, Local_IP=R7_A, Peer_IP=R3_A)  |
     |---PCRpt,CC-ID=Z,Symbolic Path Name=Class A------------------>|
     |            BPI Object(Peer AS, Local_IP=R7_A, Peer_IP=R3_A)  |

                Figure 2: Message Information and Procedures

   The Local/Peer IP address MUST be dedicated to the usage of the
   native IP TE solution, and MUST NOT be used by other BGP sessions
   that are established manually or in other ways.  If the Local IP
   Address or Peer IP Address within the BPI object is used in other
   existing BGP sessions, the PCC MUST report such an error situation
   via a PCErr message with:

      Error-type=33 (Native IP TE failure) and Error-value=1 (Local IP
      is in use), or

      Error-type=33 (Native IP TE failure )and Error-value=2 (Remote IP
      is in use).

      The detailed Error-Types and Error-Values are defined in Section 8

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   If the established BGP session is broken, the PCC MUST report such
   information via PCRpt message with the status field set to "BGP
   session down" in the associated BPI Object.  The error code field
   within the BPI object SHOULD indicate the reason that leads to the
   BGP session being down.  In the future, when the BGP session is up
   again, the PCC MUST report that as well via the PCRpt message with
   the status field set to "BGP Session Established".

6.2.  Explicit Route Establishment Procedures

   The explicit route establishment procedures can be used by PCE to
   install a route on the PCC, using the PCInitiate and PCRpt message
   pair.  Such explicit routes operate the same as static routes
   installed by network management protocols (Network Configuration
   Protocol (NETCONF)/YANG).  The procedures of such explicit route
   addition and removal MUST be controlled by the PCE in a specific
   order so that the pathways are established without loops.

   For the purpose of explicit route addition, the PCInitiate message
   ought to be sent to every router on the explicit path.  In the
   example, for the explicit route from R1 to R7, the PCInitiate message
   is sent to R1, R2 and R4, as shown in Figure 3.  For the explicit
   route from R7 to R1, the PCInitiate message is sent to R7, R4 and R2,
   as shown in Figure 5.

   When the PCC receives the EPR and the CCI object (with the R bit set
   to 0 in the SRP object) in the PCInitiate message, the PCC SHOULD
   install the explicit route to the peer in the RIB/FIB.

   When the PCC installs successfully the explicit route to the peer, it
   MUST report the result via the PCRpt messages, with the EPR object
   and the corresponding SRP and CCI objects included.

   When the PCC receives the EPR and the CCI object with the R bit set
   to 1 in the SRP object in the PCInitiate message, the PCC MUST remove
   the explicit route to the peer that is indicated by the EPR object.

   When the PCC has removed the explicit route that is indicated by this
   object, it MUST report the result via the PCRpt message, with the EPR
   object included, and the corresponding SRP and CCI object.

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                             +------------------+
                  +---------->       PCE        +
                  |          +----^-----------^-+
                  |               |           |
                  |               |           |
                  |               | +------+  |
                  +---------------|-+R3(RR)+--|-------------+
             PCInitiate/PCRpt     | +------+  |             |
                  |               |           |             |
                 +v-+      +--+   |           |   +--+    +--+
                 |R1+------+R5+---+-----------|---+R6+----+R7|
                 ++-+      +--+   |           |   +--+    +-++
                  |     PCInitiate/PCRpt  PCInitiate/PCRpt  |
                  |               |           |             |
                  |            +--v--+     +--v-+           |
                  +------------+- R2 +-----+ R4 +-----------+
                               +--+--+     +--+-+
       Figure 3: Explicit Route Establish Procedures(From R1 to R7)

   The message peers, message type, message key parameters and
   procedures in the above figures are shown below:

               +-------+                                       +-------+
               |PCC    |                                       |  PCE  |
               |R4     |                                       +-------+
        +------|       |                                           |
        | PCC  +-------+                                           |
        | R2     | |        (EPR route on R4)                      |
 +------|        | |<-PCInitiate,CC-ID=Z,Symbolic Path Name=Class A|
 |      |        | |   EPR Object(Peer Address=R7_A, Next Hop=R7_A)|
 |PCC   +--------+ |                                               |
 |R1      |  |     |----PCRpt,CC-ID=Z,Symbolic Path Name=Class A-->|
 |        |  |     |   EPR Object(Peer Address=R7_A, Next Hop=R7_A)|
 +--------+  |                                                     |
     |       |              (EPR route on R2)                      |
     |       |<--PCInitiate,CC-ID=Y,Symbolic Path Name=Class A-----|
     |       |   EPR Object(Peer Address=R7_A, Next Hop=R4_A)      |
     |       |----PCRpt,CC-ID=Y,Symbolic Path Name=Class A-------->|
     |       |   EPR Object(Peer Address=R7_A, Next Hop=R4_A)      |
     |       |                                                     |
     |                                                             |
     |                      (EPR route on R1)                      |
     |<--PCInitiate,CC-ID=X,Symbolic Path Name=Class A-------------|
     |              EPR Object(Peer Address=R7_A, Next Hop=R2_A)   |
     |---PCRpt,CC-ID=X1(Symbolic Path Name=Class A)--------------->|
     |              EPR Object(Peer Address=R7_A, Next Hop=R2_A)   |

            Figure 4: Message Information and Procedures

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                       +------------------+
                       +       PCE        <-----------+
                       +----^-----------^-+           |
                            |           |             |
                            |           |             |
                            | +------+  |             |
            +-----------------+R3(RR)+--|-------------+
            |               | +------+  |       PCInitiate/PCRpt
            |               |           |             |
           +--+      +--+   |           |   +--+    +-v+
           |R1+------+R5+---+-----------|---+R6+----+R7|
           ++-+      +--+   |           |   +--+    +-++
            |       PCInitiate/PCRpt PCInitiate/PCRpt |
            |               |           |             |
            |            +--v--+     +--v-+           |
            +------------+- R2 +-----+ R4 +-----------+
                         +--+--+     +--+-+
       Figure 5: Explicit Route Establish Procedures(From R7 to R1)

   The message peers, message type, message key parameters and
   procedures in the above figures are shown below:

               +-------+                                       +-------+
               |PCC    |                                       |  PCE  |
               |R2     |                                       +-------+
        +------|       |                                           |
        | PCC  +-------+                                           |
        | R4     | |        (EPR route on R2)                      |
 +------|        | |<-PCInitiate,CC-ID=X,Symbolic Path Name=Class A|
 |      |        | |  EPR Object(Peer Address=R1_A, Next Hop=R1_A) |
 |PCC   +--------+ |                                               |
 |R7      |  |     |----PCRpt,CC-ID=X,Symbolic Path Name=Class A-->|
 |        |  |     |  EPR Object(Peer Address=R1_A, Next Hop=R1_A) |
 +--------+  |                                                     |
     |       |              (EPR route on R4)                      |
     |       |<--PCInitiate,CC-ID=Y,Symbolic Path Name=Class A-----|
     |       |   EPR Object(Peer Address=R1_A, Next Hop=R2_A)      |
     |       |----PCRpt,CC-ID=Y,Symbolic Path Name=Class A-------->|
     |       |   EPR Object(Peer Address=R1_A, Next Hop=R2_A)      |
     |       |                                                     |
     |                                                             |
     |                      (EPR route on R7)                      |
     |<--PCInitiate,CC-ID=Z,Symbolic Path Name=Class A-------------|
     |   EPR Object(Peer Address=R1_A, Next Hop=R4_A)              |
     |---PCRpt,CC-ID=Z,Symbolic Path Name=Class A----------------->|
     |   EPR Object(Peer Address=R1_A, Next Hop=R4_A)              |

     Figure 6: Explicit Route Establish Procedures(From R7 to R1)

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   To avoid the transient loop while deploying the explicit peer route,
   the EPR object MUST be sent to the PCCs in the reverse order of the
   E2E path.  To remove the explicit peer route, the EPR object MUST be
   sent to the PCCs in the same order as the E2E path.

   To accomplish ECMP effects, the PCE can send multiple EPR/CCI objects
   to the same node, with the same route priority and peer address value
   but a different next-hop address.

   The PCC MUST verify that the next hop address is reachable.  In case
   of failure, the PCC MUST send the corresponding error via PCErr
   message, with the error information: Error-type=33 (Native IP TE
   failure), Error-value=3 (Explicit Peer Route Error).

   When the peer info is not the same as the peer info that is indicated
   in the BPI object in PCC for the same path that is identified by
   Symbolic Path Name TLV, a PCErr message MUST be reported, with the
   error information: Error-type=33 (Native IP TE failure), Error-
   value=4, EPR/BPI Peer Info Mismatch.  Note that the same error can be
   used in case no BPI is received at the PCC.

   If the PCE needs to update the path, it MUST first instruct the new
   CCI with updated EPR corresponding to the new next hop to use and
   then instruct the removal of the older CCI.

6.3.  BGP Prefix Advertisement Procedures

   The detailed procedures for BGP prefix advertisement are shown below,
   using the PCInitiate and PCRpt message pair.

   The PCInitiate message SHOULD be sent to PCC that acts as a BGP peer
   edge router only.  In the example, it is sent to R1 and R7
   respectively.

   When the PCC receives the PPA and the CCI object (with the R bit set
   to 0 in the SRP object) in the PCInitiate message, the PCC SHOULD
   send the prefixes indicated in this object to the identified BGP peer
   via the corresponding BGP session [RFC4271].

   When the PCC has successfully sent the prefixes to the appointed BGP
   peer, it MUST report the result via the PCRpt messages, with the PPA
   object and the corresponding SRP and CCI objects included.

   When the PCC receives the PPA and the CCI object with the R bit set
   to 1 in the SRP object in the PCInitiate message, the PCC MUST
   withdraw the prefixes advertisement to the peer indicated by this
   object.

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   When the PCC withdraws successfully the prefixes that are indicated
   by this object, it MUST report the result via the PCRpt message, with
   the PPA object included, and the corresponding SRP and CCI objects.

                    +------------------+
         +---------->       PCE        <-----------+
         |          +------------------+           |
         |                  +--+                   |
         +------------------+R3+-------------------+
   PCInitiate/PCRpt         +--+             PCInitiate/PCRpt
         |                                         |
        +v-+          +--+          +--+         +-v+
        |R1+----------+R5+----------+R6+---------+R7|
        ++-+          +--+          +--+         +-++
    (BGP Router)                           (BGP Router)
         |                                         |
         |                                         |
         |            +--+          +--+           |
         +------------+R2+----------+R4+-----------+
                      +--+          +--+
      Figure 7: BGP Prefix Advertisement Procedures

   The message peers, message type, message key parameters and
   procedures in the above figures are shown below:

                +-------+                                      +-------+
                |PCC    |                                      |  PCE  |
                |R1     |                                      +-------+
         +------|       |                                           |
         | PCC  +-------+                                           |
         | R7     | |   (Instruct R1 to advertise Prefix 1_A to R7) |
         |        | |<-PCInitiate,CC-ID=X,Symbolic Path Name=Class A|
         |        | |  PPA Object(Peer IP=R7_A, Prefix=1_A)         |
         +--------+ |                                               |
              |     |----PCRpt,CC-ID=X,Symbolic Path Name=Class A-->|
              |     |    PPA Object(Peer IP=R7_A, Prefix=1_A)       |
              |                                                     |
              |     (Instruct R7 to advertise Prefix 7_A to R1 )    |
              |<--PCInitiate,CC-ID=Z,Symbolic Path Name=Class A-----|
              |         PPA Object(Peer IP=R1_A, Prefix=7_A)        |
              |----PCRpt,CC-ID=Z,Symbolic Path Name=Class A-------->|
              |              PPA Object(Peer IP=R1_A, Prefix=7_A)   |
              |                                                     |

              Figure 8: Message Information and Procedures

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   The AFI/SAFI for the corresponding BGP session SHOULD match the Peer
   Prefix Advertisement Object-Type, AFI/SAFI SHOULD be 1/1 for the IPv4
   prefix and 2/1 for the IPv6 prefix.  In case of mismatch, an error:
   Error-type=33 (Native IP TE failure), Error-value=5 (BPI/PPA address
   family mismatch) MUST be reported via PCErr message.

   When the peer info is not the same as the peer info that is indicated
   in the BPI object in PCC for the same path that is identified by
   Symbolic Path Name TLV, an error: Error-type=33 (Native IP TE
   failure), Error-value=6 (PPA/BPI peer info mismatch) MUST be reported
   via the PCErr message.  Note that the same error can be used in case
   no BPI is received at the PCC.

6.4.  Selection of Raw Mode and Tunnel Mode Forwarding Strategy

   Normally, when the above procedures are finished, the user traffic
   will be forwarded via the appointed path, but the forwarding will be
   based solely on the destination of user traffic.  If there is traffic
   from different attached points to the same destination coming into
   the network, they could share the priority path which may not be the
   initial desire.  For example, as illustrated in Figure 1, the initial
   aim is to ensure traffic that enters the network via R1 and exits the
   network at R7 via R5-R6-R7.  If some traffic enters the network via
   the R2 router, passes through R5 and exits at R7, they may share the
   priority path among R5-R6-R7, which may not be the desired effect.

   The above normal traffic forwarding behavior is clarified as a Raw
   mode forwarding strategy.  Such a mode can achieve only the moderate
   traffic path control effect.  To achieve the strict traffic path
   control effect, the entry point MUST tunnel the user traffic from the
   entry point of the network to the exit point of the network, which is
   also between the BGP peer established via Section 6.1.  Such
   forwarding behavior is called the Tunnel mode forwarding strategy.
   For simplicity, the IPinIP tunnel type [RFC2003] is used between the
   BGP peers by default.

   The selection of Raw mode and Tunnel mode forwarding strategies are
   controlled via the "T" bit in BPI Object that is defined in
   Section 7.2

6.5.  Clean Up

   To remove the Native-IP state from the PCC, the PCE MUST send
   explicit CCI cleanup instructions for PPA, EPR and BPI objects
   respectively with the R flag set in the SRP object.  If the PCC
   receives a PCInitiate message but does not recognize the Native-IP
   information in the CCI, the PCC MUST generate a PCErr message with
   Error-Type=19 (Invalid operation) and Error-value=TBD2 (Unknown

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   Native-IP Info) and MUST include the SRP object to specify the error
   is for the corresponding cleanup (via a PCInitiate message).

6.6.  Other Procedures

   The handling of the state synchronization, redundant PCEs, re-
   delegation and clean up is the same as other CCIs as specified in
   [RFC9050].

7.  New PCEP Objects

   One new CCI Object type and three new PCEP objects are defined in
   this document.  All new PCEP objects are as per [RFC5440].

7.1.  CCI Object

   The Central Control Instructions (CCI) Object (defined in [RFC9050])
   is used by the PCE to specify the forwarding instructions.  This
   document defines another object type for Native-IP procedures.

   CCI Object-Type is 2 for Native-IP as 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                            CC-ID                              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Reserved             |             Flags             |
   +---------------------------------------------------------------+
   |                                                               |
   //                        Optional TLVs                        //
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

              Figure 9: CCI Object for Native IP

   The field CC-ID is as described in [RFC9050].  The following fields
   are defined for CCI Object-Type 2

   Reserved:  2 bytes, is set to zero while sending and ignored on
      receipt.

   Flags:  2 bytes, is used to carry any additional information about
      the Native-IP CCI.  Currently, no flag bits are defined.
      Unassigned flags are set to zero while sending and ignored on
      receipt.

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   Optional TLVs may be included within the CCI object body.  The
   Symbolic Path Name TLV [RFC8231] MUST be included in the CCI Object-
   Type 2 to identify the E2E TE path in the Native IP environment.

7.2.  BGP Peer Info Object

   The BGP Peer Info object is used to specify the information about the
   peer with which the PCC want to establish the BGP session.  This
   object is included and sent to the source and destination router of
   the E2E path in case there is no Route Reflection (RR) involved.  If
   the RR is used between the source and destination routers, then such
   information is sent to the source router, RR and destination router
   respectively.

   By default, the Local/Peer IP address MUST be a unicast address and
   dedicated to the usage of the native IP TE solution, and MUST NOT be
   used by other BGP sessions that are established by manual or other
   configuration mechanisms.

   BGP Peer Info Object-Class is 46

   BGP Peer Info Object-Type is 1 for IPv4 and 2 for IPv6

   The format of the BGP Peer Info object body for IPv4 (Object-Type=1)
   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                      Peer AS Number                           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   ETTL        |     Status    |   Error Code  |    Flag     |T|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                    Local IP Address                           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                    Peer IP Address                            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //                    Optional TLVs                            //
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
        Figure 10: BGP Peer Info Object Body Format for IPv4

   The format of the BGP Peer Info object body for IPv6 (Object-Type=2)
   is as follows:

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    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                      Peer AS Number                           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   ETTL        |      Status   |   Error Code  |    Flag     |T|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   |               Local IP Address (16 bytes)                     |
   |                                                               |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   |               Peer IP Address (16 bytes)                      |
   |                                                               |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //                    Optional TLVs                            //
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         Figure 11: BGP Peer Info Object Body Format for IPv6

      Peer AS Number: 4 bytes, to indicate the AS number of Remote Peer.
      Note that if 2-byte AS numbers are in use, the low-order bits (16
      through 31) is used, and the high-order bits (0 through 15) is set
      to zero.

      ETTL: 1 byte, EBGP Time To Live, to indicate the multi-hop count
      for the EBGP session.  It should be 0 and ignored when Local AS
      and Peer AS are the same.

      Status: 1 byte, Indicate BGP session status between the peers.
      Its values are defined below:

      -  0: Reserved

      -  1: BGP Session Established

      -  2: BGP Session Establishment In Progress

      -  3: BGP Session Down

      -  4-255: Reserved

      Error Code: 1 byte, Indicate the reason that the BGP session can't
      be established.

      -  0: Unspecific

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      -  1: ASes do not match, BGP Session Failure

      -  2: Peer IP can't be reached, BGP Session Failure

      -  3-255: Reserved

      Flag: 1 byte.

      -  Currently, only bit 7 (T bit) is defined.  When the T bit is
         set, the traffic SHOULD be sent in the IPinIP tunnel (Tunnel
         source is Local IP Address, tunnel destination is Peer IP
         Address).  When the T bit is cleared, the traffic is sent via
         its original source and destination address.  The Tunnel mode(T
         bit is set) is used when the operator wants to ensure only the
         traffic from the specified (entry, exit) pair, and the Raw mode
         (T bit is clear) is used when the operator wants to ensure
         traffic from any entry to the specified destination.
         Unassigned flags are set to zero while sending and ignored on
         receipt.

      Local IP Address(4/16 bytes): Unicast IP address of the local
      router, used to peer with another end router.  When Object-Type is
      1, the length is 4 bytes; when Object-Type is 2, the length is 16
      bytes.

      Peer IP Address(4/16 bytes): Unicast IP address of the peer
      router, used to peer with the local router.  When Object-Type is
      1, the length is 4 bytes; when Object-Type is 2, the length is 16
      bytes;

      Optional TLVs: TLVs that are associated with this object, can be
      used to convey other necessary information for dynamic BGP session
      establishment.  No TLVs are currently defined.

   When the PCC receives a BPI object, with Object-Type=1, it SHOULD try
   to establish a BGP session with the peer in AFI/SAFI=1/1.

   When the PCC receives a BPI object with Object-Type=2, it SHOULD try
   to establish a BGP session with the peer in AFI/SAFI=2/1.

7.3.  Explicit Peer Route Object

   The Explicit Peer Route object is defined to specify the explicit
   peer route to the corresponding peer address on each device that is
   on the E2E Native-IP TE path.  This Object ought to be sent to all
   the devices on the path that is calculated by the PCE.  Although the
   object is named as “Explicit Peer Route”, it can be seen that the
   routes it installs are simply host routes.  The use of this object to

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   install host routes for any purpose other than reaching the
   corresponding peer address on each device that is on the E2E Native-
   IP TE path is outside the scope of this specification.

   By default, the path established by this object MUST have higher
   priority than the other paths calculated by dynamic IGP protocol, and
   MUST have lower priority than the static route configured by manual
   or NETCONF or any other static means.

   Explicit Peer Route Object-Class is 47.

   Explicit Peer Route Object-Type is 1 for IPv4 and 2 for IPv6

   The format of the Explicit Peer Route object body for IPv4 (Object-
   Type=1) 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |       Route Priority        |          Reserved               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Peer IPv4 Address                       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |               Next Hop IPv4 Address to the Peer               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //                    Optional TLVs                            //
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       Figure 12: Explicit Peer Route Object Body Format for IPv4

   The format of the Explicit Peer Route object body for IPv6 (Object-
   Type=2) is as follows:

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    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |       Route Priority        |           Reserved              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   |                       Peer IPv6 Address                       |
   |                                                               |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   |                Next Hop IPv6 Address to the Peer              |
   |                                                               |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //                    Optional TLVs                            //
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       Figure 13: Explicit Peer Route Object Body Format for IPv6

      Route Priority: 2 bytes; the priority of this explicit route.  The
      higher priority SHOULD be preferred by the device.  This field is
      used to indicate the preferred path at each hop.

      Reserved: is set to zero while sending, ignored on receipt.

      Peer (IPv4/IPv6) Address: Peer Address for the BGP session (4/16
      bytes).

      Next Hop (IPv4/IPv6) Address to the Peer: To indicate the next hop
      address (4/16 bytes) to the corresponding peer address.

      Optional TLVs: TLVs that are associated with this object, can be
      used to convey other necessary information for explicit peer path
      establishment.  No TLVs are currently defined.

7.4.  Peer Prefix Advertisement Object

   The Peer Prefix Advertisement object is defined to specify the IP
   prefixes that are advertised to the corresponding peer.  This object
   needs only be included and sent to the source/destination router of
   the E2E path.

   The prefix information included in this object MUST only be
   advertised to the indicated peer, and SHOULD NOT be advertised to
   other BGP peers.

   Peer Prefix Advertisement Object-Class is 48

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   Peer Prefix Advertisement Object-Type is 1 for IPv4 and 2 for IPv6

   The format of the Peer Prefix Advertisement object body 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                  Peer IPv4 Address                            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | No. of Prefix |                  Reserved                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                  IPv4 Prefix #1                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Prefix #1 Len  |                  Reserved                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                               :                               |
   |                               :                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                  IPv4 Prefix #n                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Prefix #n Len  |                  Reserved                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //                    Optional TLVs                            //
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   Figure 14: Peer Prefix Advertisement Object Body Format for IPv4

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    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   |                  Peer IPv6 Address                            |
   |                                                               |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | No. of Prefix |                  Reserved                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                  IPv6 Prefix #1                               |
   |                                                               |
   |                                                               |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Prefix #1 Len  |                  Reserved                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                               :                               |
   |                               :                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                  IPv6 Prefix #n                               |
   |                                                               |
   |                                                               |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Prefix #n Len  |                  Reserved                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //                    Optional TLVs                            //
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    Figure 15: Peer Prefix Advertisement Object Body Format for IPv6

      Common Fields:

      No. of Prefix: 1 byte.  Identifies the number of prefixes that
         are advertised to the peer in the PPA object.

         Reserved: 3 bytes.  Ought to be set to zero while sending and
         be ignored on receipt.

         Prefix Len: 1 byte.  Identifies the length of the prefix.

         Optional TLVs: TLVs that are associated with this object, can
         be used to convey other necessary information for prefix
         advertisement.  No TLVs are currently defined.

      For IPv4:

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      Peer IPv4 Address: 4 bytes.  Identifies the peer IPv4 address
         that the associated prefixes will be sent to.

         IPv4 Prefix: 4 bytes.  Identifies the prefix that will be sent
         to the peer identified by Peer IPv4 Address.

      For IPv6:

         Peer IPv6 Address: 16 bytes.  Identifies the peer IPv6 address
         that the associated prefixes will be sent to.

         IPv6 Prefix: Identifies the prefix that will be sent to the
         peer identified by Peer IPv6 Address.

      If in the future, a requirement is identified to advertise IPv4
      prefixes toward an IPv6 peering address, or IPv6 prefixes towards
      an IPv4 peering address, then a new Peer Prefix Advertisement
      Object-Types can be defined for these purposes.

8.  New Error-Types and Error-Values Defined

   A PCEP-ERROR object is used to report a PCEP error and is
   characterized by an Error-Type that specifies that type of error and
   an Error-value that provides additional information about the error.
   An additional Error-Type and several Error-values are defined to
   represent the errors related to the newly defined objects that are
   related to Native IP TE procedures.

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         +============+==========+=====================================+
         | Error-Type | Meaning  | Error-value                         |
         +=======+===============+=====================================+
         | 33    | Native IP TE failure                                |
         |       |                                                     |
         +-------+---------------+-------------------------------------+
         |       |               |0:Unassigned                         |
         +-------+---------------+-------------------------------------+
         |       |               |1:Local IP is in use                 |
         +-------+---------------+-------------------------------------+
         |       |               |2:Remote IP is in use                |
         +-------+---------------+-------------------------------------+
         |       |               |3:Explicit Peer Route Error          |
         +-------+---------------+-------------------------------------+
         |       |               |4:EPR/BPI Peer Info mismatch         |
         +-------+---------------+-------------------------------------+
         |       |               |5:BPI/PPA Address Family mismatch    |
         +-------+---------------+-------------------------------------+
         |       |               |6:PPA/BPI Peer Info mismatch         |
         +-------+---------------+-------------------------------------+
         | 6     | Mandatory Object missing                            |
         |       |                                                     |
         +-------+---------------+-------------------------------------+
         |       |               |19:Native IP object missing          |
         +-------+---------------+-------------------------------------+
         | 10    | Reception of an invalid object                      |
         |       |                                                     |
         +-------+---------------+-------------------------------------+
         |       |               |39:PCECC NATIVE-IP-TE-CAPABILITY bit |
         |       |               |is not set                           |
         +-------+---------------+-------------------------------------+
         | 19    | Invalid Operation                                   |
         |       |                                                     |
         +-------+---------------+-------------------------------------+
         |       |               |22:Only one BPI, EPR or PPA object   |
         |       |               |can be included in this message      |
         +-------+---------------+-------------------------------------+
         |       |               |TBD1:Attempted Native-IP operations  |
         |       |               |when the capability was not          |
         |       |               | advertised                          |
         +-------+---------------+-------------------------------------+
         |       |               |TBD2:Unknown Native-IP Info          |
         +-------+---------------+-------------------------------------+
              Figure 16: Newly defined Error-Type and Error-Value

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9.  BGP Considerations

   This document defines the procedures and objects to create the BGP
   sessions and advertise the associated prefixes dynamically.  Only the
   key information, for example, peer IP addresses, and peer AS numbers
   are exchanged via the PCEP protocol.  Other parameters that are
   needed for the BGP session setup SHOULD be derived from their default
   values.

   When the PCE sends out the PCInitiate message with the BPI object
   embedded to establish the BGP session between the PCC peers, the PCC
   SHOULD report the BGP session status.  For instance, the PCC could
   respond with "BGP Session Establishment In Progress" initially and on
   session establishment send another PCRpt message with the state
   updated to "BGP Session Established".  If there is any error during
   the BGP session establishment, the PCC SHOULD indicate the reason
   with the appropriate status value set in the BPI object.

   Upon receiving such key information, the BGP module on the PCC SHOULD
   try to accomplish the task appointed by the PCEP protocol and report
   the successful status to the PCEP modules after the session is set
   up.

   There is no influence on the current implementation of BGP Finite
   State Machine (FSM).  The PCEP focuses only on the success and
   failure status of the BGP session and acts upon such information
   accordingly.

   The error-handling procedures related to incorrect BGP parameters are
   specified in Section 6.1, Section 6.2, and Section 6.3.

10.  Deployment Considerations

   The information transferred in this document is mainly used for the
   BGP session setup, explicit route deployment and the prefix
   distribution.  The planning, allocation and distribution of the peer
   addresses within IGP needs to be accomplished in advance and they are
   out of the scope of this document.

   The communication of PCE and PCC described in this document MUST
   follow the state synchronization procedures described in [RFC8232],
   treat the three newly defined objects (BPI, EPR and PPA) associated
   with the same symbolic path name as the attribute of the same path in
   the LSP-DB (LSP State Database).

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   When PCE detects one or some of the PCCs are out of its control, it
   MUST recompute and redeploy the traffic engineering path for native
   IP on the currently active PCCs.  The PCE MUST ensure the avoidance
   of the possible transient loop in such node failure when it deploys
   the explicit peer route on the PCCs.

   In case of a PCE failure, a new PCE can gain control over the central
   controller instructions as described in [RFC9050].

   As per the PCEP procedures in [RFC8281], the State Timeout Interval
   timer is used to ensure that a PCE failure does not result in
   automatic and immediate disruption for the services.  Similarly, as
   per [RFC9050], the central controller instructions are not removed
   immediately upon PCE failure.  Instead, they could be re-delegated to
   the new PCE before the expiration of this timer, or be cleaned up on
   the expiration of this timer.  This allows for network clean up
   without manual intervention.  The PCC supports the removal of CCI as
   one of the behaviors applied on the expiration of the State Timeout
   Interval timer.

11.  Manageability Considerations

11.1.  Control of Function and Policy

   A PCE or PCC implementation SHOULD allow the PCECC Native-IP
   capability to be enabled/disabled as part of the global
   configuration.

11.2.  Information and Data Models

   [RFC7420] describes the PCEP MIB; this MIB could be extended to get
   the PCECC Native-IP capability status.  The PCEP YANG
   [I-D.ietf-pce-pcep-yang] module could be extended to enable/disable
   the PCECC Native-IP capability.

11.3.  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].  The operator relies on existing IP liveness
   detection and monitoring.

11.4.  Verify Correct Operations

   Verification of the mechanisms defined in this document can be built
   on those already listed in [RFC5440], [RFC8231] and [RFC9050].
   Further, the operator needs to be able to verify the status of BGP
   sessions and prefix advertisements.

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11.5.  Requirements on Other Protocols

   Mechanisms defined in this document require the interaction with BGP.
   Section 9 describes in detail the considerations regarding the BGP.
   During the BGP session establishment, the Local/Peer IP address MUST
   be dedicated to the usage of the native IP TE solution, and MUST NOT
   be used by other BGP sessions that are established manually or in
   other ways.

11.6.  Impact on Network Operations

   [RFC8821] describes the various deployment considerations in CCDR
   architecture and their impact on network operations.

12.  Security Considerations

   In this setup, the BGP sessions, prefix advertisement, and explicit
   peer route establishment are all controlled by the PCE.  See
   [RFC4271] for security consideration of classical BGP implementation,
   and [RFC4272] for classical BGP vulnerabilities analysis.  Security
   considerations in [RFC5440]for basic PCEP protocol, [RFC8231] for
   PCEP extension for stateful PCE and [RFC8281] for PCE-Initiated LSP
   setup SHOULD be considered.  To prevent a bogus PCE from sending
   harmful messages to the network nodes, the network devices SHOULD
   authenticate the PCE and ensure a secure communication channel
   between them.  Thus, the mechanisms described in [RFC8253] for the
   usage of TLS for PCEP and [RFC9050] for protection against malicious
   PCEs SHOULD be used.

   If suitable default values as discussed in Section 9 aren't enough
   and securing the BGP transport is required(for example, the TCP-AO
   [RFC5925], it can be provided through the addition of optional TLVs
   to the BGP Peer Info object that conveys the necessary additional
   information (for example, a key chain [RFC8177]name).

13.  IANA Considerations

13.1.  Path Setup Type Registry

   [RFC8408] created a sub-registry within the "Path Computation Element
   Protocol (PCEP) Numbers" registry called "PCEP Path Setup Types".
   IANA is requested to allocate a new code point within this sub-
   registry, as follows:

   Value          Description                        Reference
   4              Native IP TE Path                  This document

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13.2.  PCECC-CAPABILITY sub-TLV's Flag field

   Editorial Note (To be removed by RFC Editor): This experimental track
   document is allocating a code point in the registry under the
   standards action registry which is not allowed.
   [I-D.ietf-pce-iana-update] updates the registration policy to IETF
   review allowing for this allocation.  Note that an early allocation
   was made when the document was being progressed in the standards
   track.  At the time of publication, please remove this note and the
   reference to [I-D.ietf-pce-iana-update].

   [RFC9050] created a sub-registry within the "Path Computation Element
   Protocol (PCEP) Numbers" registry to manage the value of the PCECC-
   CAPABILITY sub-TLV's 32-bit Flag field.  IANA is requested to
   allocate a new bit position within this registry, as follows:

   Bit       Name                   Reference
   30        NATIVE IP              This document

13.3.  PCEP Object

   IANA is requested to allocate new codepoints in the "PCEP Objects"
   sub-registry as follows:

   Object-Class Value   Name                        Reference
   44                   CCI Object                  This document
                        Object-Type
                          2: Native IP

   46                BGP Peer Info                  This document
                        Object-Type
                          1: IPv4 address
                          2: IPv6 address

   47                Explicit Peer Route            This document
                        Object-Type
                          1: IPv4 address
                          2: IPv6 address

   48                Peer Prefix Advertisement      This document
                        Object-Type
                          1: IPv4 address
                          2: IPv6 address

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13.4.  PCEP-Error Object

   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 for the following errors:

Error-Type  Meaning              Error-value
6      Mandatory Object missing
                                 19:Native IP object missing

10    Reception of an invalid object
                                 39:PCECC NATIVE-IP-TE-CAPABILITY bit
                                    is not set

19    Invalid Operation
                                 22:Only one BPI, EPR or PPA object can
                                    be included in this message
                                 TBD1:Attempted Native-IP operations
                                    when the capability was not advertised
                                 TBD2:Unknown Native-IP Info

33     Native IP TE failure
                           1:Local IP is in use
                           2:Remote IP is in use
                           3:Explicit Peer Route Error
                           4:EPR/BPI Peer Info mismatch
                           5:BPI/PPA Address Family mismatch
                           6:PPA/BPI Peer Info mismatch

   The reference for the new Error-type/value should be set to this
   document.

13.5.  CCI Object Flag Field

   IANA is requested to create a new sub-registry to manage the 16-bits
   Flag field of the new CCI Object called "CCI Object Flag Field for
   Native-IP".  New values are to be assigned by IETF review [RFC8126].
   Each bit should be tracked with the following qualities:

      bit number (counting from bit 0 as the most significant bit, and
      bit 15 as the lest significant bit)

      capability description

      defining RFC

   Currently, no flags are assigned.

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13.6.  BPI Object Status Code

   IANA is requested to create a new sub-registry "BPI Object Status
   Code Field" within the "Path Computation Element Protocol (PCEP)
   Numbers".  New values are assigned by IETF review [RFC8126].  Each
   value should be tracked with the following qualities: value, meaning,
   and defining RFC.  The following values are defined in this document:

  Value           Meaning                                    Reference
      0           Reserved                                 This document
      1           BGP Session Established                  This document
      2           BGP Session Establishment In Progress    This document
      3           BGP Session Down                         This document
      4-255       Unassigned                               This document

13.7.  BPI Object Error Code

   IANA is requested to create a new sub-registry "BPI Object Error Code
   Field" within the "Path Computation Element Protocol (PCEP) Numbers".
   New values are assigned by IETF review [RFC8126].  Each value should
   be tracked with the following qualities: value, meaning, and defining
   RFC.  The following values are defined in this document:

  Value     Meaning                                          Reference
      0     Reserved                                       This document
      1     ASes does not match, BGP Session Failure       This document
      2     Peer IP can't be reached, BGP Session Failure  This document
      3-255 Unassigned                                     This document

13.8.  BPI Object Flag Field

   IANA is requested to create a new sub-registry "BPI Object Flag
   Field" within the "Path Computation Element Protocol (PCEP) Numbers".
   New values are to be assigned by IETF review [RFC8126].  Each bit
   should be tracked with the following qualities:

      bit number (counting from bit 0 as the most significant bit)

      capability description

      defining RFC

   The following values are defined in this document:

   Bit             Meaning                            Reference
   0-6             Unassigned
   7               T (IPnIP) bit                      This document

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14.  Contributor

   Dhruv Dhody has contributed to this document.

15.  Acknowledgement

   Thanks Mike Koldychev, Susan Hares, Siva Sivabalan and Adam Simpson
   for their valuable suggestions and comments.

16.  References

16.1.  Normative References

   [I-D.ietf-pce-iana-update]
              Dhody, D. and A. Farrel, "Update to the IANA PCEP
              Registration Procedures and Allowing Experimental Error
              Codes", Work in Progress, Internet-Draft, draft-ietf-pce-
              iana-update-01, 27 August 2024,
              <https://datatracker.ietf.org/doc/html/draft-ietf-pce-
              iana-update-01>.

   [RFC2003]  Perkins, C., "IP Encapsulation within IP", RFC 2003,
              DOI 10.17487/RFC2003, October 1996,
              <https://www.rfc-editor.org/info/rfc2003>.

   [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>.

   [RFC4271]  Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
              Border Gateway Protocol 4 (BGP-4)", RFC 4271,
              DOI 10.17487/RFC4271, January 2006,
              <https://www.rfc-editor.org/info/rfc4271>.

   [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>.

   [RFC5511]  Farrel, A., "Routing Backus-Naur Form (RBNF): A Syntax
              Used to Form Encoding Rules in Various Routing Protocol
              Specifications", RFC 5511, DOI 10.17487/RFC5511, April
              2009, <https://www.rfc-editor.org/info/rfc5511>.

   [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>.

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

   [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,
              <https://www.rfc-editor.org/info/rfc8126>.

   [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>.

   [RFC8232]  Crabbe, E., Minei, I., Medved, J., Varga, R., Zhang, X.,
              and D. Dhody, "Optimizations of Label Switched Path State
              Synchronization Procedures for a Stateful PCE", RFC 8232,
              DOI 10.17487/RFC8232, September 2017,
              <https://www.rfc-editor.org/info/rfc8232>.

   [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>.

   [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>.

   [RFC8408]  Sivabalan, S., Tantsura, J., Minei, I., Varga, R., and J.
              Hardwick, "Conveying Path Setup Type in PCE Communication
              Protocol (PCEP) Messages", RFC 8408, DOI 10.17487/RFC8408,
              July 2018, <https://www.rfc-editor.org/info/rfc8408>.

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   [RFC9050]  Li, Z., Peng, S., Negi, M., Zhao, Q., and C. Zhou, "Path
              Computation Element Communication Protocol (PCEP)
              Procedures and Extensions for Using the PCE as a Central
              Controller (PCECC) of LSPs", RFC 9050,
              DOI 10.17487/RFC9050, July 2021,
              <https://www.rfc-editor.org/info/rfc9050>.

16.2.  Informative References

   [I-D.ietf-pce-pcep-yang]
              Dhody, D., Beeram, V. P., Hardwick, J., and J. Tantsura,
              "A YANG Data Model for Path Computation Element
              Communications Protocol (PCEP)", Work in Progress,
              Internet-Draft, draft-ietf-pce-pcep-yang-25, 21 May 2024,
              <https://datatracker.ietf.org/doc/html/draft-ietf-pce-
              pcep-yang-25>.

   [RFC3209]  Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
              and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
              Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001,
              <https://www.rfc-editor.org/info/rfc3209>.

   [RFC4272]  Murphy, S., "BGP Security Vulnerabilities Analysis",
              RFC 4272, DOI 10.17487/RFC4272, January 2006,
              <https://www.rfc-editor.org/info/rfc4272>.

   [RFC5036]  Andersson, L., Ed., Minei, I., Ed., and B. Thomas, Ed.,
              "LDP Specification", RFC 5036, DOI 10.17487/RFC5036,
              October 2007, <https://www.rfc-editor.org/info/rfc5036>.

   [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>.

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

   [RFC8283]  Farrel, A., Ed., Zhao, Q., Ed., Li, Z., and C. Zhou, "An
              Architecture for Use of PCE and the PCE Communication
              Protocol (PCEP) in a Network with Central Control",
              RFC 8283, DOI 10.17487/RFC8283, December 2017,
              <https://www.rfc-editor.org/info/rfc8283>.

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   [RFC8735]  Wang, A., Huang, X., Kou, C., Li, Z., and P. Mi,
              "Scenarios and Simulation Results of PCE in a Native IP
              Network", RFC 8735, DOI 10.17487/RFC8735, February 2020,
              <https://www.rfc-editor.org/info/rfc8735>.

   [RFC8821]  Wang, A., Khasanov, B., Zhao, Q., and H. Chen, "PCE-Based
              Traffic Engineering (TE) in Native IP Networks", RFC 8821,
              DOI 10.17487/RFC8821, April 2021,
              <https://www.rfc-editor.org/info/rfc8821>.

Authors' Addresses

   Aijun Wang
   China Telecom
   Beiqijia Town, Changping District
   Beijing
   Beijing, 102209
   China
   Email: wangaijun@tsinghua.org.cn

   Boris Khasanov
   MTS Web Services (MWS)
   Andropova av.,18/9 115432
   Moscow
   Email: bhassanov@yahoo.com

   Sheng Fang
   Huawei Technologies
   Huawei Bld., No.156 Beiqing Rd.
   Beijing
   China
   Email: fsheng@huawei.com

   Ren Tan
   Huawei Technologies
   Huawei Bld., No.156 Beiqing Rd.
   Beijing
   China
   Email: tanren@huawei.com

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   Chun Zhu
   ZTE Corporation
   50 Software Avenue, Yuhua District
   Nanjing
   Jiangsu, 210012
   China
   Email: zhu.chun1@zte.com.cn

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