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<rfc xmlns:xi="http://www.w3.org/2001/XInclude" category="std" docName="draft-ietf-pce-pcep-color-12" number="9863" updates="" obsoletes="" ipr="trust200902" submissionType="IETF" consensus="true"> consensus="true" tocInclude="true" tocDepth="3" symRefs="true" sortRefs="true" version="3" xml:lang="en">

  <front>
    <title abbrev="PCEP Color">Path Computation Element Protocol (PCEP) Extension for Color</title>
    <seriesInfo name="RFC" value="9863"/>
    <author initials="B." surname="Rajagopalan" fullname="Balaji Rajagopalan">
      <organization>Juniper Networks</organization>
      <address>
        <email>balajir@juniper.net</email>
      </address>
    </author>
    <author initials="V." surname="Beeram" fullname="Vishnu Pavan Beeram">
      <organization>Juniper Networks</organization>
      <address>
        <email>vbeeram@juniper.net</email>
      </address>
    </author>
    <author initials="S." surname="Peng" fullname="Shaofu Peng">
      <organization>ZTE Corporation</organization>
      <address>
        <email>peng.shaofu@zte.com.cn</email>
      </address>
    </author>
    <author fullname="Mike Koldychev" initials="M." surname="Koldychev">
      <organization>Ciena Corporation</organization>
      <address>
        <email>mkoldych@proton.me</email>
      </address>
    </author>
    <author fullname="Gyan Mishra" initials="G." surname="Mishra">
      <organization>Verizon Communications Inc.</organization>
      <address>
        <email>gyan.s.mishra@verizon.com</email>
      </address>
    </author>
    <date month="September" year="2025"/>

    <area>Routing</area>
    <workgroup>PCE Working Group</workgroup>

    <area>RTG</area>
    <workgroup>pce</workgroup>

    <keyword>color</keyword>

    <abstract>
      <t>
      Color is a 32-bit numerical (unsigned integer) attribute used to
      associate a Traffic Engineering (TE) tunnel or policy with an intent
      or objective. For example, a TE Tunnel constructed to deliver low
      latency services and whose path is optimized for delay can be tagged
      with a color that represents "low latency." This document specifies
      extensions to the Path Computation Element Protocol (PCEP) to carry
      the color attribute.
      </t>
    </abstract>
  </front>
  <middle>
    <section title="Introduction" anchor='intro'> anchor="intro">
      <name>Introduction</name>
      <t>
      A Traffic Engineering (TE) tunnel (<xref target="RFC3209"/>) <xref target="RFC3209"/> or Segment Routing
      (SR) policy (<xref target="RFC9256"/>) <xref target="RFC9256"/> can be associated
      with an intent or objective (e.g., low latency) by tagging it with a color. This
      color attribute is used as a guiding criterion for mapping services onto the TE
      tunnel (<xref target="RFC9012"/>) <xref target="RFC9012"/> or SR policy (<xref target="RFC9256"/>). <xref target="RFC9256"/>.
      The term color "color" used in this document must not be interpreted as the 'thread color' "thread color"
      specified in <xref target="RFC3063"/> or the 'resource color' "resource color" (also referred to as 'link color') "link color")
      specified in <xref target="RFC3630"/>, <xref target="RFC5329"/>,
      <xref target ="RFC5305"/> target="RFC5305"/>, and <xref target="RFC7308"/>.
      </t>
      <t>
      <xref target="RFC8231"/> specifies extensions to the Path Computation Element
      Protocol (PCEP) that enable the deployment of a stateful Path Computation Element
      (PCE) model. These extensions allow a Path Computation Client (PCC) to delegate
      control of the Label Switched Paths (LSPs) associated with its TE Tunnels to a
      stateful PCE. <xref target="RFC8281"/> specifies extensions that allow a PCE to
      instantiate and manage PCE-initiated LSPs on a PCC under the stateful PCE model.
      <xref target="RFC8664"/> specifies extensions that enable stateful control of SR
      paths via PCEP.
      </t>
      <t>
      This document introduces extensions to PCEP to allow a color tag
      to be assigned to any TE path operated under a stateful PCE model
      (including those set up using RSVP-TE <xref target="RFC8408"/> or
      Segment Routing <xref target ="RFC8664"/>). target="RFC8664"/>).
      The only exception where the extensions defined in
      this document MUST NOT <bcp14>MUST NOT</bcp14> be used to carry the color attribute is for SR paths
      established using the extensions defined in <xref target="I-D.ietf-pce-segment-routing-policy-cp"/>. target="RFC9862"/>.
      For these SR paths, the associated color is already included as part of the SR
      policy identifier encoding.
      </t>
      <t>
      The mechanism employed by the PCC for mapping services onto a TE path
      associated with a color attribute is outside the scope of this document, as
      is any other use of the color tag.
      </t>

   <section title="Requirements Language">
       <t>The
      <section>
        <name>Requirements Language</name>
        <t>
    The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
       "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", "<bcp14>MUST</bcp14>", "<bcp14>MUST NOT</bcp14>", "<bcp14>REQUIRED</bcp14>", "<bcp14>SHALL</bcp14>", "<bcp14>SHALL
    NOT</bcp14>", "<bcp14>SHOULD</bcp14>", "<bcp14>SHOULD NOT</bcp14>", "<bcp14>RECOMMENDED</bcp14>", "<bcp14>NOT RECOMMENDED</bcp14>",
    "<bcp14>MAY</bcp14>", and "OPTIONAL" "<bcp14>OPTIONAL</bcp14>" in this document are to be interpreted as
    described in BCP 14 BCP&nbsp;14 <xref target="RFC2119"/> <xref target="RFC8174"/>
    when, and only when, they appear in all capitals, as shown here.
        </t>
      </section>
    </section>

    <section title="Protocol Operation">
    <section>
      <name>Protocol Operation</name>
      <t>
        When the PCEP session is created, a PCEP (PCE/PCC) speaker sends
        an Open message with an OPEN object that contains the
        STATEFUL-PCE-CAPABILITY TLV, as defined in <xref target="RFC8231"/>. A
        STATEFUL-PCE-CAPABILITY TLV Flag (See (see <xref target="Color-Cap"/>)
        is introduced in this document to enable the PCEP speaker to advertise color
        capability.
      </t>
      <t>
        In PCRpt, PCUpd, and PCInitiate messages, the LSP object (<xref target="RFC8231"/>, <xref target="RFC8281"/>) target="RFC8231"/>  <xref target="RFC8281"/>
        is a mandatory inclusion and is used to carry information specific to the target LSP. A TLV called the Color TLV
        (see <xref target="TLV-Format"/>), which MAY <bcp14>MAY</bcp14> be carried in the LSP object, is
        introduced in this document to carry the color attribute associated with the LSP.
        Only one COLOR TLV SHOULD <bcp14>SHOULD</bcp14> be included in the LSP object.  If the COLOR TLV appears
        in the LSP object more than once, only the first occurrence is processed, and any
        others MUST <bcp14>MUST</bcp14> be ignored.
      </t>

<!--[rfced] We note that this document uses terms such as "PCEP Peer",
"TE Tunnel", and "SR Policy" with the second word capitalized.  If
the intention is to use these terms with a specific meaning, would
you like to add a sentence stating where to find that definition?
For example:

Perhaps:
  This document uses the following terms:

    PCEP Peer as defined in [RFC5440]
    SR Policy as defined in [RFC8402]
-->
      <t>
        A PCEP speaker that has advertised color capability MUST NOT <bcp14>MUST NOT</bcp14>
        send Color TLV encoded in the LSP object to a PCEP Peer that has not advertised color
        capability. A PCEP speaker that advertises both color capability and
        SR Policy Association <xref target="RFC9862"/> capability (<xref target="I-D.ietf-pce-segment-routing-policy-cp"/>) MUST
        NOT <bcp14>MUST
        NOT</bcp14> send Color TLV encoded in the LSP object for SR Paths.
        The Color TLV is ignored if it shows up in the LSP object of a message which that
        carries an ASSOCIATION object of type SR Policy Association (<xref target="I-D.ietf-pce-segment-routing-policy-cp"/>). <xref target="RFC9862"/>.
        The color encoded in the SR Policy Association takes precedence in such a scenario.
      </t>
      <t>
	If a PCC is unable to honor a color value passed in a PCUpd
        or a PCInitiate message, the PCC MUST <bcp14>MUST</bcp14> reject the message
        and send a PCErr message with Error-type=19 Error-Type=19 (Invalid Operation)
        and error-value=TBD1 Error-value=31 (Invalid color). This is expected behavior
        in scenarios where a PCC implementation does not support a color
        value of zero for specific path setup types, and it receives that
        value in the COLOR TLV of a PCUpd or a PCInitiate message.
      </t>
      <t>
        When LSPs that belong to the same TE tunnel are within the
        same Path Protection Association Group <xref target="RFC8745"/>,
        they are all expected to have the same color attached to them.
        If a PCEP speaker
	determines inconsistency in the color associated with the LSPs
        belonging to the same Path Protection Association Group, it MUST <bcp14>MUST</bcp14>
        reject the message carrying the inconsistent color and send a
        PCErr message with Error-type=19 Error-Type=19 (Invalid Operation) and
        error-value=TBD2
        Error-value=32 (Inconsistent color).
      </t>
    </section>
    <section title="Protocol Extensions" anchor="Proto-Ext">
      <name>Protocol Extensions</name>
      <section title="Color Capability" anchor="Color-Cap">
        <name>Color Capability</name>
        <t>
        Section 7.1.1 of
        <xref target="RFC8231"/> target="RFC8231" sectionFormat="of" section="7.1.1"/> defines
        STATEFUL-PCE-CAPABILITY TLV flags. The following flag is used to
        indicate if the speaker supports color capability:
        </t>
      <t>
        <list>
          <t>
            C-bit

	<dl spacing="normal" newline="false">
          <dt>C-bit (Bit 20): A 20):</dt><dd>A PCE/PCC indicates that it supports the
          color capability defined in this document by setting this bit.
          </t>
        </list>
      </t> bit.</dd>
	</dl>

      </section>
      <section title="Color TLV" anchor="TLV-Format">
        <name>Color TLV</name>
        <figure anchor="color-tlv" title="Color TLV"> anchor="color-tlv">
          <name>Color TLV</name>
          <artwork xml:space="preserve" align="left"> align="left"><![CDATA[
   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                      |          Length=4             |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                             Color                             |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      </artwork>
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+]]></artwork>
        </figure>
      <t>

<!-- [rfced] In many RFCs, the text following a TLV diagram is a definition
list rather than a paragraph. Would you like to update this as follows?

Current:
   Type has the value 67.  Length carries a value of 4.  The 'color' "color"
   field is 4-bytes long, 4 bytes long and carries the actual color value (specified
   as an unsigned integer).  A color value of zero is allowed.

Perhaps:
   Type:  67

   Length:  4

   Color:  4-byte field that carries the actual color value (specified
      as an unsigned integer). A value of zero is allowed.
-->

        <t>
	  Type has the value 67. Length carries a value of 4.
	  The "Color" field is 4 bytes long and carries the actual color value
          (specified as an unsigned integer). A Color value of zero is allowed.
        </t>
      </section>
    </section>
    <section title='Security Considerations' anchor='sec-con'> anchor="sec-con">
      <name>Security Considerations</name>
      <t>
	This document defines a TLV for color and a flag for
	color capability negotiation, which do not add any security
	concerns beyond those discussed in <xref target='RFC5440'/>, target="RFC5440"/>,
	<xref target='RFC8231'/> target="RFC8231"/>, and <xref target='RFC8281'/>. target="RFC8281"/>.
      </t>
      <t>
	An unauthorized PCE may maliciously associate the LSP with an
	incorrect color. The procedures described in <xref
	target='RFC8253'/> target="RFC8253"/> and <xref target='RFC9325'/> target="RFC9325"/> can be used to
	protect against this attack.
      </t>
    </section>
    <section title='Manageability Considerations' anchor='mgmt-con'> anchor="mgmt-con">
      <name>Manageability Considerations</name>
      <t>
      This section follows the advice and guidance of <xref target='RFC6123'/>. target="RFC6123"/>.
      </t>
      <section title='Control anchor="mgmt-con-cfp">
        <name>Control of Function through Configuration and Policy' anchor='mgmt-con-cfp'> Policy</name>
        <t>
      An implementation supporting this document SHOULD <bcp14>SHOULD</bcp14> allow the operator
      to turn on and off the PCEP color capability advertisement (<xref target='Color-Cap'/>). target="Color-Cap"/>).
      An implementation supporting this document SHOULD <bcp14>SHOULD</bcp14> allow the configuration
      of color assignment to a TE Tunnel or an SR Policy. A PCC MAY <bcp14>MAY</bcp14> have a
      local policy configuration that specifies how the color tag is used.
      This policy configuration is outside the scope of this document.
        </t>
      </section>
      <section title='Information anchor="mgmt-con-idm">
        <name>Information and Data Models' anchor='mgmt-con-idm'> Models</name>
        <t>
      An implementation supporting this document SHOULD <bcp14>SHOULD</bcp14> allow the inclusion of color
      in the data model used to retrieve the operational state of a TE tunnel or an SR policy.
      The YANG model in <xref target="I-D.ietf-teas-yang-te"/> could be used to retrieve the
      operational state of a TE tunnel, and the YANG model in <xref target="I-D.ietf-spring-sr-policy-yang"/>
      could be used to retrieve the operational state of an SR policy.
        </t>
      </section>
      <section title='Liveness anchor="mgmt-con-ldm">
        <name>Liveness Detection and Monitoring' anchor='mgmt-con-ldm'> Monitoring</name>
        <t>
      The extensions defined in this document do not require any additional
      liveness detection and monitoring support.  See <xref target='RFC5440'/> target="RFC5440"/> and
      <xref target='RFC5886'/> target="RFC5886"/> for more information.
        </t>
      </section>
      <section title='Verifying anchor="mgmt-con-vco">
        <name>Verifying Correct Operation' anchor='mgmt-con-vco'> Operation</name>
        <t>
      The operator MAY <bcp14>MAY</bcp14> retrieve the operational state of TE Paths to verify if they are tagged with the correct intended color.
        </t>
      </section>
      <section title='Requirements anchor="mgmt-con-prot">
        <name>Requirements on Other Protocols' anchor='mgmt-con-prot'> Protocols</name>
        <t>
      This document places no explicit requirements on other protocols.
        </t>
      </section>
      <section title='Impact anchor="mgmt-con-ino">
        <name>Impact on Network Operation' anchor='mgmt-con-ino'> Operation</name>
        <t>
      The impact on network operations depends on how the color tag is used in the deployment. This is outside the scope of this document.
        </t>
      </section>
    </section>
    <section anchor="IANA" title="IANA Considerations">
      <section title="PCEP anchor="IANA">
      <name>IANA Considerations</name>
      <section>
        <name>PCEP TLV Type Indicator"> Indicator</name>
        <t>
         This document introduces
         IANA has assigned a value in the
         "PCEP TLV Type Indicators" registry of the
         "Path Computation Element Protocol (PCEP) Numbers" registry group as follows:
   <figure>
   <artwork align="left"><![CDATA[
 Value    Description             Reference
 ----------------------------------------------
 67       Color                   This document
   ]]></artwork>
   </figure>
         Note: The code point specified for the TLV Type Indicator
         is an early allocation by IANA.
        </t>

	<table>
	  <thead><tr><th>Value</th><th>Description</th><th>Reference</th></tr></thead>
	  <tbody><tr><td>67</td><td>Color</td><td>RFC 9863</td></tr></tbody>
	</table>

      </section>
      <section title="STATEFUL-PCE-CAPABILITY
      <section>
        <name>STATEFUL-PCE-CAPABILITY TLV Flag Field"> Field</name>
        <t>
         This document introduces
         IANA has assigned a bit value in the
         "STATEFUL-PCE-CAPABILITY TLV Flag Field" registry of the
         "Path Computation Element Protocol (PCEP) Numbers" registry group as follows:
   <figure>
   <artwork align="left"><![CDATA[
 Value    Description             Reference
 ----------------------------------------------
 20       COLOR-CAPABILITY        This document
   ]]></artwork>
   </figure>
         Note: The code point specified for the STATEFUL-PCE-CAPABILITY
         TLV Flag is an early allocation by IANA.
        </t>
      </section>
      <section title="PCEP-Error Object">
	<table>
	  <thead><tr><th>Value</th><th>Description</th><th>Reference</th></tr></thead>
	  <tbody><tr><td>20</td><td>COLOR-CAPABILITY</td><td>RFC 9863</td></tr></tbody>
	</table>
      </section>
      <section>
        <name>PCEP-Error Object</name>
        <t>
      This document introduces
      IANA has assigned two Error-values for Error-Type=19 (Invalid Operation)
      within the "PCEP-ERROR Object Error Types and Values" registry of the "Path
      Computation Element Protocol (PCEP) Numbers" registry group as follows:
   <figure>
   <artwork align="left"><![CDATA[
 Error-  Meaning            Error-value               Reference
 Type
 ------------------------------------------------------------------
 19      Invalid Operation  TBD1:
        </t>

	<table>
	  <thead>
	    <tr>
	      <th>Error-Type</th>
	      <th>Meaning</th>
              <th>Error-value</th>
              <th>Reference</th>
	    </tr>
	  </thead>
	  <tbody>
	    <tr>
	      <td rowspan="2">19</td>
	      <td rowspan="2">Invalid Operation</td>
	      <td>31: Invalid Color       This document
                            TBD2: Color</td>
	      <td>RFC 9863</td>
	    </tr>
	    <tr>
              <td>32: Inconsistent Color  This document
   ]]></artwork>
   </figure>
      </t> Color</td>
	      <td>RFC 9863</td>
	    </tr>
	  </tbody>
	</table>

      </section>
      <section title="LSP-ERROR-CODE
      <section>
        <name>LSP-ERROR-CODE TLV Error Code Field"> Field</name>
        <t>
   An earlier
   A draft version of this document added an error code in the
   "LSP-ERROR-CODE TLV Error Code Field" registry of the
   "Path Computation Element Protocol (PCEP) Numbers"
   registry group, which was also early allocated by the IANA.
        </t>
        <t>
	  IANA is requested to cancel the early allocation made which is not
   needed anymore.  As per the instructions from the chairs, please mark has marked it as deprecated.
        </t>
         <t>
   <figure>
   <artwork align="left"><![CDATA[
   Value    Meaning                         Reference
   ------------------------------------------------------
   9        Deprecated
	<table>
	  <thead><tr><th>Value</th><th>Meaning</th><th>Reference</th></tr></thead>
	  <tbody>
	    <tr>
	      <td>9</td>
	      <td>Deprecated (Unsupported Color)  This document
   ]]></artwork>
   </figure>
         </t> Color)</td>
	      <td>RFC 9863</td>
	    </tr>
	  </tbody>
	</table>
      </section>
    </section>

    <section title="Implementation Status">
   <t>[Note to the RFC Editor - remove this section before publication, as
   well as remove the reference to RFC 7942.]</t>

   <t>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 <xref target="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.</t>

   <t>According to <xref target="RFC7942"/>, "this will allow reviewers and working groups
   to assign due consideration to documents that have the benefit of
   running code, which may serve

  </middle>
  <back>

    <displayreference target="I-D.ietf-spring-sr-policy-yang" to="SR-POLICY-YANG"/>
    <displayreference target="I-D.ietf-teas-yang-te" to="YANG-TE"/>
    <references>
      <name>References</name>
      <references>
        <name>Normative References</name>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.2119.xml"/>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8174.xml"/>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.5440.xml"/>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8231.xml"/>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8253.xml"/>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8281.xml"/>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8408.xml"/>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8664.xml"/>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8745.xml"/>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.9012.xml"/>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.9325.xml"/>

        <reference anchor="RFC9862" target="https://www.rfc-editor.org/info/rfc9862">
          <front>
            <title>Path Computation Element Communication Protocol (PCEP) Extensions for Segment Routing (SR) Policy Candidate Paths</title>
            <author initials="M." surname="Koldychev" fullname="Mike Koldychev">
              <organization>Ciena Corporation</organization>
            </author>
            <author initials="S." surname="Sivabalan" fullname="Siva Sivabalan">
              <organization>Ciena Corporation</organization>
            </author>
            <author initials="S." surname="Sidor" fullname="Samuel Sidor">
              <organization>Cisco Systems, Inc.</organization>
            </author>
            <author initials="C." surname="Barth" fullname="Colby Barth">
              <organization>Juniper Networks, Inc.</organization>
            </author>
            <author initials="S." surname="Peng" fullname="Shuping Peng">
              <organization>Huawei Technologies</organization>
            </author>
            <author initials="H." surname="Bidgoli" fullname="Hooman Bidgoli">
              <organization>Nokia</organization>
            </author>
            <date month="September" year="2025"/>
          </front>
          <seriesInfo name="RFC" value="9862"/>
          <seriesInfo name="DOI" value="10.17487/RFC9862"/>
        </reference>
      </references>
      <references>
        <name>Informative References</name>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.3063.xml"/>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.3209.xml"/>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.3630.xml"/>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.5305.xml"/>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.5329.xml"/>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.5886.xml"/>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.6123.xml"/>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.7308.xml"/>
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.9256.xml"/>

<!-- [I-D.ietf-teas-yang-te]
draft-ietf-teas-yang-te-38
IESG State: I-D Exists 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 07/15/25
-->
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml3/reference.I-D.ietf-teas-yang-te.xml"/>
<!-- [I-D.ietf-spring-sr-policy-yang]
draft-ietf-spring-sr-policy-yang-05
IESG State: I-D Exists as
   they see fit".</t>

   <t> At the time of publication of this version, there are no known
   implementations. Juniper Networks has plans to implement the
   extensions defined in this document.</t>
    </section> 07/15/25
-->
        <xi:include href="https://bib.ietf.org/public/rfc/bibxml3/reference.I-D.ietf-spring-sr-policy-yang.xml"/>
      </references>
    </references>

    <section title='Acknowledgments'>
      <t>
	The numbered="false">
      <name>Acknowledgments</name>
      <t>The authors would like to thank Kaliraj Vairavakkalai, Colby
	Barth, Natrajan Venkataraman, Tarek Saad, Dhruv Dhody, Adrian Farrel,
        Andrew Stone, Diego Achaval, and Narasimha Kommuri <contact fullname="Kaliraj
      Vairavakkalai"/>, <contact fullname="Colby Barth"/>, <contact
      fullname="Natrajan Venkataraman"/>, <contact fullname="Tarek Saad"/>,
      <contact fullname="Dhruv Dhody"/>, <contact fullname="Adrian Farrel"/>,
      <contact fullname="Andrew Stone"/>, <contact fullname="Diego Achaval"/>,
      and <contact fullname="Narasimha Kommuri"/> for their review and
	suggestions.
      </t>
      suggestions.</t>
    </section>

    <section title='Contributors'> numbered="false">
      <name>Contributors</name>
      <t>The following people have contributed to this document:</t>
    <author initials="Q." surname="Xiong"

      <contact fullname="Quan Xiong">
        <organization>ZTE Corporation</organization>
        <address>
          <email>xiong.quan@zte.com.cn</email>
        </address>
    </author>
      </contact>

    </section>

</middle>

<back>
  <references title='Normative References'>
    &RFC2119;
    &RFC8174;
    &RFC5440;
    &RFC8231;
    &RFC8253;
    &RFC8281;
    &RFC8408;
    &RFC8664;
    &RFC8745;
    &RFC9012;
    &RFC9325;
    <?rfc include='reference.I-D.ietf-pce-segment-routing-policy-cp.xml'?>
  </references>
  <references title='Informative References'>
    &RFC3063;
    &RFC3209;
    &RFC3630;
    &RFC5305;
    &RFC5329;
    &RFC5886;
    &RFC6123;
    &RFC7308;
    &RFC7942;
    &RFC9256;
    <?rfc include='reference.I-D.ietf-teas-yang-te.xml'?>
    <?rfc include='reference.I-D.ietf-spring-sr-policy-yang.xml'?>
  </references>

  </back>

<!-- [rfced] Throughout the text, the following terminology appears to be used
inconsistently. Please review these occurrences and let us know if/how they
may be made consistent.

   COLOR TLV vs. Color TLV
   OPEN vs. open (one instance of each)
   TE Tunnel vs. TE tunnel
   SR Policy vs. SR policy
-->

<!-- [rfced] Please review the "Inclusive Language" portion of the online
Style Guide <https://www.rfc-editor.org/styleguide/part2/#inclusive_language>
and let us know if any changes are needed.  Updates of this nature typically
result in more precise language, which is helpful for readers.

Note that our script did not flag any words in particular, but this should
still be reviewed as a best practice.
-->

</rfc>