<?xml version="1.0"encoding="US-ASCII"?>encoding="UTF-8"?> <!DOCTYPE rfcSYSTEM "rfc2629.dtd"> <?rfc toc="yes"?> <?rfc tocompact="yes"?> <?rfc tocdepth="3"?> <?rfc tocindent="yes"?> <?rfc symrefs="yes"?> <?rfc sortrefs="yes"?> <?rfc comments="yes"?> <?rfc inline="yes"?> <?rfc compact="yes"?> <?rfc subcompact="no"?>[ <!ENTITY nbsp " "> <!ENTITY zwsp "​"> <!ENTITY nbhy "‑"> <!ENTITY wj "⁠"> ]> <rfc xmlns:xi="http://www.w3.org/2001/XInclude" submissionType="IETF" category="std" consensus="true" docName="draft-ietf-opsawg-ipfix-srv6-srh-14"ipr="trust200902">number="9487" ipr="trust200902" obsoletes="" updates="" xml:lang="en" tocInclude="true" tocDepth="3" symRefs="true" sortRefs="true" version="3"> <front> <title abbrev="IPFIX Segment Routing overIPv6">Export of Segment Routing over IPv6 Information in IP Flow Information Export (IPFIX)</title>IPv6">Export of Segment Routing over IPv6 Information in IP Flow Information Export (IPFIX)</title> <seriesInfo name="RFC" value="9487"/> <author fullname="Thomas Graf" initials="T" surname="Graf"> <organization>Swisscom</organization> <address> <postal> <street>Binzring 17</street> <city>Zurich</city> <code>8045</code> <country>Switzerland</country> </postal> <email>thomas.graf@swisscom.com</email> </address> </author> <author fullname="Benoit Claise" initials="B" surname="Claise"> <organization>Huawei</organization> <address> <email>benoit.claise@huawei.com</email> </address> </author> <author fullname="Pierre Francois" initials="P." surname="Francois"> <organization>INSA-Lyon</organization> <address> <postal> <street/> <city>Lyon</city> <region/> <code/> <country>France</country> </postal> <phone/><facsimile/><email>pierre.francois@insa-lyon.fr</email> <uri/> </address> </author> <dateday="25" month="May"month="November" year="2023"/> <area>ops</area> <workgroup>opsawg</workgroup> <abstract> <t>This document introduces new IP Flow Information Export (IPFIX) Information Elements (IEs) to identify a set of information related to Segment Routing over IPv6 (SRv6)related informationsuch as data contained in a Segment Routing Header (SRH), the SRv6 control plane, and the SRv6endpointEndpoint behavior that traffic is being forwarded with.</t> </abstract> </front> <middle> <section anchor="Introduction"title="Introduction">numbered="true" toc="default"> <name>Introduction</name> <t>A dedicated Routing Extension Header, calledSegment"Segment Routing Header(SRH),(SRH)", is defined in <xreftarget="RFC8754"/>target="RFC8754" format="default"/> for use of Segment Routing(SR)over IPv6 (SRv6) data plane.</t> <t>Also, three routing protocol extensions, <xreftarget="I-D.ietf-lsr-ospfv3-srv6-extensions">OSPFv3</xref>,target="I-D.ietf-lsr-ospfv3-srv6-extensions" format="default">OSPFv3</xref>, <xreftarget="RFC9352">IS-IS</xref>target="RFC9352" format="default">IS-IS</xref>, and <xreftarget="RFC8669">BGPtarget="RFC8669" format="default">BGP Prefix SegmentIdentifiers(Prefix-SIDs)</xref> andIdentifiers (Prefix-SIDs)</xref>; the <xreftarget="I-D.ietf-pce-segment-routing-ipv6">Pathtarget="I-D.ietf-pce-segment-routing-ipv6" format="default">Path Computation Element Communication Protocol (PCEP)Extension</xref>Extension</xref>; and the <xreftarget="RFC9256">Segmenttarget="RFC9256" format="default">Segment Routing Policy</xref> are defined to propagate Segment Identifiers (SIDs).</t> <t>SRv6segment endpointSegment Endpoint behaviors describe how packets should be processed by SRv6 Segment Endpoint Nodes. Such behaviors are defined in <xreftarget="RFC8986"/>.</t>target="RFC8986" format="default"/>.</t> <t>This document specifies eleven new IPFIX Information Elements (IEs) and one new subregistry within the "IPFIX Information Elements" registry <xreftarget="RFC7012"/>,target="RFC7012" format="default"/>, for SRv6 purposes.</t> <t>These IEs are used to export the SRv6 active segment and its control plane protocol, the SRv6 Segment List, the next SRv6 node and its type, and the numbers of SRv6 segments left.</t> <t>Some examples are provided inAppendix A.</t><xref target="Encoding-Example" format="default"/>.</t> </section> <section anchor="notation"title="Terminology"> <t>Thenumbered="true" toc="default"> <name>Terminology</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 inBCP 14BCP 14 <xref target="RFC2119"/> <xref target="RFC8174"/> when, and only when, they appear in all capitals, as shownhere.</t>here. </t> <t>This document makes use of the terms defined in <xreftarget="RFC7011"/>,target="RFC7011" format="default"/>, <xreftarget="RFC8402"/>target="RFC8402" format="default"/>, and <xreftarget="RFC8754"/>.</t>target="RFC8754" format="default"/>.</t> <t>The following terms are used as defined in <xreftarget="RFC7011"/>:</t> <t><list style="symbols"> <t>IPFIX</t> <t>IPFIXtarget="RFC7011" format="default"/>:</t> <ul spacing="normal"> <li>IPFIX</li> <li>IPFIX InformationElements</t> <t>Template</t> <t>Template Record</t> <t>Options Template</t> <t>OptionsElements</li> <li>Template</li> <li>Template Record</li> <li>Options Template</li> <li>Options TemplateRecord</t> <t>Data Record</t> <t>Data Set</t> </list></t>Record</li> <li>Data Record</li> <li>Data Set</li> </ul> <t>The following terms are used as defined in <xreftarget="RFC8402"/>:</t> <t><list style="symbols"> <t>Segmenttarget="RFC8402" format="default"/>:</t> <ul spacing="normal"> <li>Segment Routing(SR)</t> <t>Segment</t> <t>Segment List</t> <t>Active Segment</t> <t>Segment(SR)</li> <li>Segment</li> <li>Segment List</li> <li>Active Segment</li> <li>Segment Identifier(SID)</t> <t>SRv6</t> <t>SRv6 SID</t> </list></t>(SID)</li> <li>SRv6</li> <li>SRv6 SID</li> </ul> <t>The following terms are used as defined in <xreftarget="RFC8754"/>:</t> <t><list style="symbols"> <t>Segmenttarget="RFC8754" format="default"/>:</t> <ul spacing="normal"> <li>Segment Routing Header(SRH)</t> <t>SR(SRH)</li> <li>SR SourceNode</t> <t>Transit Node</t> <t>SRNode</li> <li>Transit Node</li> <li>SR Segment EndpointNode</t> <t>Reduced SRH</t> <t>Segments Left</t> <t>Last Entry</t> </list></t>Node</li> <li>Reduced SRH</li> <li>Segments Left</li> <li>Last Entry</li> </ul> </section> <section anchor="IE"title="Newnumbered="true" toc="default"> <name>New IPFIX IPv6 SRH InformationElements">Elements</name> <t>This section specifies the new IPFIX IPv6 SRHIEs.<list style="hanging"> <t hangText="srhFlagsIPv6"><vspace blankLines="0"/>IEs.</t> <dl newline="true" spacing="normal"> <dt>srhFlagsIPv6</dt> <dd>The 8-bitflagsFlags field defined in the SRH(Section 2 of <xref target="RFC8754"/>).</t> <t hangText="srhTagIPv6"><vspace blankLines="0"/>(<xref target="RFC8754" sectionFormat="of" section="2"/>).</dd> <dt>srhTagIPv6</dt> <dd>The 16-bittagTag field defined in the SRH(Section 2 of <xref target="RFC8754"/>).(<xref target="RFC8754" sectionFormat="of" section="2"/>). A tag is used to mark a packet as part of a class or group of packets sharing the same set ofproperties.</t> <t hangText="srhSegmentIPv6"><vspace blankLines="0"/>properties.</dd> <dt>srhSegmentIPv6</dt> <dd>The 128-bit IPv6 address that representsaan SRv6segment.</t> <t hangText="srhActiveSegmentIPv6"><vspace blankLines="0"/>segment.</dd> <dt>srhActiveSegmentIPv6</dt> <dd>The 128-bit IPv6 address that represents the active SRv6segment.</t> <t hangText="srhSegmentIPv6BasicList"><vspace blankLines="0"/> Orderedsegment.</dd> <dt>srhSegmentIPv6BasicList</dt> <dd> The ordered basicList <xreftarget="RFC6313"/>target="RFC6313" format="default"/> of zero or more 128-bit IPv6 addresses in the SRH that represents the SRv6 Segment List. As specified inSection 2 of<xreftarget="RFC8754"/>,target="RFC8754" sectionFormat="of" section="2"/>, the Segment List is encoded starting from the last segment of the SR Policy. That is, the first element of the Segment List (Segment List[0]) contains the last segment of the SR Policy, the second element contains the penultimate segment of the SR Policy, and soon.</t> <t hangText="srhSegmentIPv6ListSection"><vspace blankLines="0"/>on.</dd> <dt>srhSegmentIPv6ListSection</dt> <dd> The SRH Segment List as defined inSection 2 of<xreftarget="RFC8754"/>target="RFC8754" sectionFormat="of" section="2"/> as a series of octets inIPFIX.</t> <t hangText="srhSegmentsIPv6Left"><vspace blankLines="0"/>IPFIX.</dd> <dt>srhSegmentsIPv6Left</dt> <dd>The 8-bit unsigned integerdefiningthat defines the number of segments remaining to reach the end of the Segment List from the SRH, as specified by the "Segments Left" field inSection 4.4 of<xreftarget="RFC8200"/>target="RFC8200" sectionFormat="of" section="4.4"/> and as mentionedpart ofin the SRHin Section 2part of <xreftarget="RFC8754"/>).</t> <t hangText="srhIPv6Section"><vspace blankLines="0"/> Exposes thetarget="RFC8754" sectionFormat="of" section="2"/>.</dd> <dt>srhIPv6Section</dt> <dd> The SRH and its TLVs as specified inSection 2 of<xreftarget="RFC8754"/>target="RFC8754" sectionFormat="of" section="2"/> as a series of octets inIPFIX.</t> <t hangText="srhIPv6ActiveSegmentType"><vspace blankLines="0"/> DesignatorIPFIX.</dd> <dt>srhIPv6ActiveSegmentType</dt> <dd> The designator of the routing protocol or PCEP extension where the active SRv6 segment has been learnedfrom.</t> <t hangText="srhSegmentIPv6LocatorLength"><vspace blankLines="0"/>from.</dd> <dt>srhSegmentIPv6LocatorLength</dt> <dd> The length of the SRH segment IPv6 locatorlengthspecified as the number of significant bits. Together withsrhSegmentIPv6srhSegmentIPv6, it enables the calculation of the SRv6Locator.</t> <t hangText="srhSegmentIPv6EndpointBehavior"><vspace blankLines="0"/>Locator.</dd> <dt>srhSegmentIPv6EndpointBehavior</dt> <dd>The 16-bit unsigned integer that representsaan SRv6 Endpoint behavior as perSection 4 of<xreftarget="RFC8986"/>.</t> </list></t>target="RFC8986" sectionFormat="of" section="4"/>.</dd> </dl> <t>Note that the srhSegmentIPv6, srhSegmentIPv6LocatorLength, and srhSegmentIPv6EndpointBehavior IPFIX IEs are genericfields,fields to be used in the context of IPFIX Options Templates or IPFIX Structured Data <xreftarget="RFC6313"/>.</t>target="RFC6313" format="default"/>.</t> </section> <section anchor="Sample-Use-Cases"title="Samplenumbered="true" toc="default"> <name>Sample UseCases">Cases</name> <t>The IPFIX IEs srhSegmentIPv6BasicList(TBD5)(496) or alternatively srhSegmentIPv6ListSection(TBD6),(497), srhActiveSegmentIPv6(TBD4),(495), srhSegmentsIPv6Left(TBD7), srhIPv6ActiveSegmentType(TBD9),(498), srhIPv6ActiveSegmentType (500), and forwardingStatus (89) <xreftarget="RFC7270"/>target="RFC7270" format="default"/> <xreftarget="IANA-IPFIX"/>, andtarget="IANA-IPFIX" format="default"/> as well as some existing counterinformationsinformation <xreftarget="IANA-IPFIX"/> providingtarget="IANA-IPFIX" format="default"/> provide answers to the following questions (amongst others):</t><t><list style="symbols"> <t>How<ul spacing="normal"> <li>How many packets steered withaan SR policy are forwarded or dropped using SRv6 in anetwork?</t> <t>Ifnetwork?</li> <li>If dropped, for whichreasons?</t> <t>Whatreasons?</li> <li>What is the current active segment and its associated control planeprotocol?</t> <t>Whatprotocol?</li> <li>What is the SRv6 SegmentList?</t> <t>WhatList?</li> <li>What is the next SRv6 node and itstype?</t> <t>Howtype?</li> <li>How many SRv6 segments areleft?</t> </list></t>left?</li> </ul> </section> <section anchor="IANA"title="IANA Considerations"> <t>Note to the RFC-Editor:</t> <t><list style="symbols"> <t>Please replace TBD1 - TBD17 with the values allocated by IANA</t> <t>Please replace the [RFC-to-be] with the RFC number assigned to this document</t> </list></t>numbered="true" toc="default"> <name>IANA Considerations</name> <section anchor="sec-new-ies"title="New IPFIX IPv6 SRHnumbered="true" toc="default"> <name>IPFIX InformationElements"> <t>This document requests IANA to addElements Registry</name> <t>IANA has added the following new IEs(<xref target="sec-new-ies"/>)to the "IPFIX Information Elements" registry <xreftarget="RFC7012"/> availabletarget="RFC7012" format="default"/> at <xreftarget="IANA-IPFIX"/>.</t> <t>Table 1 lists the new IPv6 SRH IEs:</t> <t><figure> <artwork><![CDATA[ +-------+--------------------------------+ |Element| Name | | ID | | +-------+--------------------------------+ | TBD1 | srhFlagsIPv6 | | | | +-------+--------------------------------+ | TBD2 | srhTagIPv6 | | | | +-------+--------------------------------+ | TBD3 | srhSegmentIPv6 | | | | +-------+--------------------------------+ | TBD4 | srhActiveSegmentIPv6 | | | | +-------+--------------------------------+ | TBD5 | srhSegmentIPv6BasicList | | | | +-------+--------------------------------+ | TBD6 | srhSegmentIPv6ListSection | | | | +-------+--------------------------------+ | TBD7 | srhSegmentsIPv6Left | | | | +-------+--------------------------------+ | TBD8 | srhIPv6Section | | | | +-------+--------------------------------+ | TBD9 | srhIPv6ActiveSegmentType | | | | +-------+--------------------------------+ | TBD10 | srhSegmentIPv6LocatorLength | | | | +-------+--------------------------------+ | TBD11 | srhSegmentIPv6EndpointBehavior | | | | +-------+--------------------------------+ Table 1: New IPv6 SRH IEs in the "IPFIXtarget="IANA-IPFIX" format="default"/>:</t> <table anchor="table1" align="center"> <name>IPFIX InformationElements" Registry ]]></artwork> </figure></t>Elements Registry</name> <thead> <tr> <th>ElementID</th> <th>Name</th> </tr> </thead> <tbody> <tr> <td>492</td> <td>srhFlagsIPv6</td> </tr> <tr> <td>493</td> <td>srhTagIPv6</td> </tr> <tr> <td>494</td> <td>srhSegmentIPv6</td> </tr> <tr> <td>495</td> <td>srhActiveSegmentIPv6</td> </tr> <tr> <td>496</td> <td>srhSegmentIPv6BasicList</td> </tr> <tr> <td>497</td> <td>srhSegmentIPv6ListSection</td> </tr> <tr> <td>498</td> <td>srhSegmentsIPv6Left</td> </tr> <tr> <td>499</td> <td>srhIPv6Section</td> </tr> <tr> <td>500</td> <td>srhIPv6ActiveSegmentType</td> </tr> <tr> <td>501</td> <td>srhSegmentIPv6LocatorLength</td> </tr> <tr> <td>502</td> <td>srhSegmentIPv6EndpointBehavior</td> </tr> </tbody> </table> <section anchor="IANAsrhFlagsIPv6"title="srhFlagsIPv6"> <dl>numbered="true" toc="default"> <name>srhFlagsIPv6</name> <dl spacing="compact" newline="false"> <dt>ElementID:</dt> <dd>492</dd> <dt>Name:</dt> <dd>srhFlagsIPv6</dd></dl> <dl> <dt>ElementID:</dt> <dd>TBD1</dd> </dl> <dl><dt>Abstract Data Type:</dt> <dd>unsigned8</dd> <dt>Data Type Semantics:</dt> <dd>flags</dd> <dt>Description:</dt> <dd>The 8-bitflagsFlags field defined in the SRH(Section 2 of <xref target="RFC8754"/>).(<xref target="RFC8754" sectionFormat="of" section="2"/>). Assigned flags and their meanings are provided in the "Segment Routing Header Flags" IANA registry.</dd></dl> <dl> <dt>Abstract Data Type:</dt> <dd>unsigned8</dd> </dl> <dl> <dt>Data Type Semantics:</dt> <dd>flags</dd> </dl> <dl><dt>Additional Information:</dt> <dd>See the assignments in the "Segment Routing Header Flags"IANAregistry athttps://www.iana.org/assignments/ipv6-parameters/ipv6-parameters.xhtml#segment-routing-header-flags.<eref target="https://www.iana.org/assignments/ipv6-parameters" brackets="angle"/>. See alsoRFC8754<xref target="RFC8754" format="default"/> for the SRH specification.</dd></dl> <dl><dt>Reference:</dt><dd>[RFC-to-be]</dd><dd>RFC 9487</dd> </dl> </section> <section anchor="IANAsrhTagIPv6"title="srhTagIPv6"> <dl>numbered="true" toc="default"> <name>srhTagIPv6</name> <dl spacing="compact" newline="false"> <dt>ElementID:</dt> <dd>493</dd> <dt>Name:</dt> <dd>srhTagIPv6</dd></dl> <dl> <dt>ElementID:</dt> <dd>TBD2</dd> </dl> <dl><dt>Abstract Data Type:</dt> <dd>unsigned16</dd> <dt>Data Type Semantics:</dt> <dd>identifier</dd> <dt>Description:</dt> <dd>The 16-bittagTag field defined in the SRH(Section 2 of <xref target="RFC8754"/>).(<xref target="RFC8754" sectionFormat="of" section="2"/>). A tag is used to mark a packet as part of a class or group of packets sharing the same set of properties.</dd></dl> <dl> <dt>Abstract Data Type:</dt> <dd>unsigned16</dd> </dl> <dl> <dt>Data Type Semantics:</dt> <dd>identifier</dd> </dl> <dl><dt>Additional Information:</dt> <dd>SeeSection 2 of<xreftarget="RFC8754"/>target="RFC8754" sectionFormat="of" section="2"/> for more details about thetag.</dd> </dl> <dl>Tag.</dd> <dt>Reference:</dt><dd>[RFC-to-be]</dd><dd>RFC 9487</dd> </dl> </section> <section anchor="IANAsrhSegmentIPv6"title="srhSegmentIPv6"> <dl>numbered="true" toc="default"> <name>srhSegmentIPv6</name> <dl spacing="compact" newline="false"> <dt>ElementID:</dt> <dd>494</dd> <dt>Name:</dt> <dd>srhSegmentIPv6</dd></dl> <dl> <dt>ElementID:</dt> <dd>TBD3</dd> </dl> <dl><dt>Abstract Data Type:</dt> <dd>ipv6Address</dd> <dt>Data Type Semantics:</dt> <dd>default</dd> <dt>Description:</dt> <dd>The 128-bit IPv6 address that representsaan SRv6 segment.</dd></dl> <dl> <dt>Abstract Data Type:</dt> <dd>ipv6address</dd> </dl> <dl> <dt>Data Type Semantics:</dt> <dd>default</dd> </dl> <dl><dt>Additional Information:</dt> <dd>Specified inSection 1 of<xreftarget="RFC8402"/>target="RFC8402" sectionFormat="of" section="1"/> and mentioned in "Segment List" inSection 2 of<xreftarget="RFC8754"/>.</dd> </dl> <dl>target="RFC8754" sectionFormat="of" section="2"/>.</dd> <dt>Reference:</dt><dd>[RFC-to-be]</dd><dd>RFC 9487</dd> </dl> </section> <section anchor="IANAsrhActiveSegmentIPv6"title="srhActiveSegmentIPv6"> <dl>numbered="true" toc="default"> <name>srhActiveSegmentIPv6</name> <dl spacing="compact" newline="false"> <dt>ElementID:</dt> <dd>495</dd> <dt>Name:</dt> <dd>srhActiveSegmentIPv6</dd></dl> <dl> <dt>ElementID:</dt> <dd>TBD4</dd> </dl> <dl><dt>Abstract Data Type:</dt> <dd>ipv6Address</dd> <dt>Data Type Semantics:</dt> <dd>default</dd> <dt>Description:</dt> <dd>The 128-bit IPv6 address that represents the active SRv6 segment.</dd></dl> <dl> <dt>Abstract Data Type:</dt> <dd>ipv6address</dd> </dl> <dl> <dt>Data Type Semantics:</dt> <dd>default</dd> </dl> <dl><dt>Additional Information:</dt> <dd>SeeSection 2 of<xreftarget="RFC8402"/>target="RFC8402" sectionFormat="of" section="2"/> for the definition ofactive segment.</dd> </dl> <dl>"active segment".</dd> <dt>Reference:</dt><dd>[RFC-to-be]</dd><dd>RFC 9487</dd> </dl> </section> <section anchor="IANAsrhSegmentIPv6BasicList"title="srhSegmentIPv6BasicList"> <dl>numbered="true" toc="default"> <name>srhSegmentIPv6BasicList</name> <dl newline="false" spacing="compact"> <dt>ElementID:</dt> <dd>496</dd> <dt>Name:</dt> <dd>srhSegmentIPv6BasicList</dd></dl> <dl> <dt>ElementID:</dt> <dd>TBD5</dd> </dl> <dl><dt>Abstract Data Type:</dt> <dd>basicList</dd> <dt>Data Type Semantics:</dt> <dd>list</dd> <dt>Description:</dt> <dd>TheOrderedordered basicList[RFC6313]<xref target="RFC6313" format="default"/> of zero or more 128-bit IPv6 addresses in the SRH that represents the SRv6 Segment List. As specified inSection 2 of<xreftarget="RFC8754"/>,target="RFC8754" sectionFormat="of" section="2"/>, the Segment List is encoded starting from the last segment of the SR Policy. That is, the first element of the Segment List (Segment List[0]) contains the last segment of the SR Policy, the second element contains the penultimate segment of the SR Policy, and so on.</dd></dl> <dl> <dt>Abstract Data Type:</dt> <dd>basicList</dd> </dl> <dl> <dt>Data Type Semantics:</dt> <dd>list</dd> </dl> <dl><dt>Additional Information:</dt> <dd>SeeSection 2 of<xreftarget="RFC8754"/>target="RFC8754" sectionFormat="of" section="2"/> for more details about the SRv6 Segment List.</dd></dl> <dl><dt>Reference:</dt><dd>[RFC-to-be]</dd><dd>RFC 9487</dd> </dl> </section> <section anchor="IANAsrhSegmentIPv6ListSection"title="srhSegmentIPv6ListSection"> <dl>numbered="true" toc="default"> <name>srhSegmentIPv6ListSection</name> <dl spacing="compact" newline="false"> <dt>ElementID:</dt> <dd>497</dd> <dt>Name:</dt> <dd>srhSegmentIPv6ListSection</dd></dl> <dl> <dt>ElementID:</dt> <dd>TBD6</dd> </dl> <dl><dt>Abstract Data Type:</dt> <dd>octetArray</dd> <dt>Data Type Semantics:</dt> <dd>default</dd> <dt>Description:</dt> <dd>TheSRHSRv6 Segment List as defined inSection 2 of<xreftarget="RFC8754"/>target="RFC8754" sectionFormat="of" section="2"/> as a series of octets in IPFIX.</dd></dl> <dl> <dt>Abstract Data Type:</dt> <dd>octetArray</dd> </dl> <dl> <dt>Data Type Semantics:</dt> <dd>default</dd> </dl> <dl><dt>Additional Information:</dt> <dd>SeeSection 2 of<xreftarget="RFC8754"/>target="RFC8754" sectionFormat="of" section="2"/> for more details about the SRv6 Segment List.</dd></dl> <dl><dt>Reference:</dt><dd>[RFC-to-be]</dd><dd>RFC 9487</dd> </dl> </section> <section anchor="IANAsrhSegmentsIPv6Left"title="srhSegmentsIPv6Left"> <dl>numbered="true" toc="default"> <name>srhSegmentsIPv6Left</name> <dl spacing="compact" newline="false"> <dt>ElementID:</dt> <dd>498</dd> <dt>Name:</dt> <dd>srhSegmentsIPv6Left</dd></dl> <dl> <dt>ElementID:</dt> <dd>TBD7</dd> </dl> <dl><dt>Abstract Data Type:</dt> <dd>unsigned8</dd> <dt>Data Type Semantics:</dt> <dd>quantity</dd> <dt>Description:</dt><dd>8-bit<dd>The 8-bit unsigned integer defining the number of segments remaining to reach the end of the Segment Listinfrom the SRH.</dd></dl> <dl> <dt>Abstract Data Type:</dt> <dd>unsigned8</dd> </dl> <dl> <dt>Data Type Semantics:</dt> <dd>quantity</dd> </dl> <dl><dt>Additional Information:</dt> <dd>Specified by the "Segments Left" field inSection 4.4 of<xreftarget="RFC8200"/>target="RFC8200" sectionFormat="of" section="4.4"/> and mentioned inSection 2 of<xreftarget="RFC8754"/>).</dd> </dl> <dl>target="RFC8754" sectionFormat="of" section="2"/>.</dd> <dt>Reference:</dt><dd>[RFC-to-be]</dd><dd>RFC 9487</dd> </dl> </section> <section anchor="IANAsrhIPv6Section"title="srhIPv6Section"> <dl>numbered="true" toc="default"> <name>srhIPv6Section</name> <dl spacing="compact" newline="false"> <dt>ElementID:</dt> <dd>499</dd> <dt>Name:</dt> <dd>srhIPv6Section</dd></dl> <dl><dt>Abstract Data Type:</dt> <dd>octetArray</dd> <dt>Data Type Semantics:</dt> <dd>default</dd> <dt>Description:</dt> <dd>The SRH and its TLVs as defined inSection 2 of<xreftarget="RFC8754"/>target="RFC8754" sectionFormat="of" section="2"/> as a series of octets in IPFIX.</dd></dl> <dl> <dt>Abstract Data Type:</dt> <dd>octetArray</dd> </dl> <dl> <dt>Data Type Semantics:</dt> <dd>default</dd> </dl> <dl><dt>Additional Information:</dt> <dd>SeeSection 2 of<xreftarget="RFC8754"/>target="RFC8754" sectionFormat="of" section="2"/> for more details about the structure of an SRH.</dd></dl> <dl><dt>Reference:</dt><dd>[RFC-to-be]</dd><dd>RFC 9487</dd> </dl> </section> <section anchor="IANAsrhIPv6ActiveSegmentType"title="srhIPv6ActiveSegmentType"> <dl>numbered="true" toc="default"> <name>srhIPv6ActiveSegmentType</name> <dl spacing="compact" newline="false"> <dt>ElementID:</dt> <dd>500</dd> <dt>Name:</dt> <dd>srhIPv6ActiveSegmentType</dd></dl> <dl> <dt>ElementID:</dt> <dd>TBD9</dd> </dl> <dl><dt>Abstract Data Type:</dt> <dd>unsigned8</dd> <dt>Data Type Semantics:</dt> <dd>identifier</dd> <dt>Description:</dt> <dd>The designator of the routing protocol or PCEP extensionfromwhere the active SRv6 segment has been learned from. Values for this Information Element are listed in the "IPFIX IPv6 SRH Segmenttype" subregistry, see <xref target="IANA-IPFIX"/>.</dd> </dl> <dl> <dt>Abstract Data Type:</dt> <dd>unsigned8</dd> </dl> <dl> <dt>DataTypeSemantics:</dt> <dd>identifier</dd> </dl> <dl>(Value 500)" subregistry.</dd> <dt>Additional Information:</dt> <dd>See the assigned types in[IPFIX IPv6 SRH Segment Type Subregistry].</dd> <dt>Note to IANA:</dt> <dd>Please replace [IPFIXthe "IPFIX IPv6 SRH SegmentType Subregistry] with the URL of the IANA subregistry.</dd> </dl> <dl>(Value 500)" registry at <eref target="https://www.iana.org/assignments/ipfix" brackets="angle"/>.</dd> <dt>Reference:</dt><dd>[RFC-to-be]</dd><dd>RFC 9487</dd> </dl> </section> <section anchor="IANAsrhSegmentIPv6LocatorLength"title="srhSegmentIPv6LocatorLength"> <dl>numbered="true" toc="default"> <name>srhSegmentIPv6LocatorLength</name> <dl spacing="compact" newline="false"> <dt>ElementID:</dt> <dd>501</dd> <dt>Name:</dt> <dd>srhSegmentIPv6LocatorLength</dd></dl> <dl> <dt>ElementID:</dt> <dd>TBD10</dd> </dl> <dl><dt>Data Type Semantics:</dt> <dd>default</dd> <dt>Description:</dt> <dd>The length of the SRH segment IPv6 locatorlengthspecified as the number of significant bits. Together withsrhSegmentIPv6srhSegmentIPv6, it enables the calculation of the SRv6 Locator.</dd></dl> <dl> <dt>Abstract Data Type:</dt> <dd>unsigned8</dd> </dl> <dl> <dt>Data Type Semantics:</dt> <dd>default</dd> </dl> <dl><dt>Additional Information:</dt> <dd>SeeSection 3.1 of<xreftarget="RFC8986"/>target="RFC8986" sectionFormat="of" section="3.1"/> for more details about the SID format.</dd></dl> <dl><dt>Reference:</dt><dd>[RFC-to-be]</dd><dd>RFC 9487</dd> </dl> </section> <section anchor="IANAsrhSegmentIPv6EndpointBehavior"title="srhSegmentIPv6EndpointBehavior"> <dl>numbered="true" toc="default"> <name>srhSegmentIPv6EndpointBehavior</name> <dl spacing="compact" newline="false"> <dt>ElementID:</dt> <dd>502</dd> <dt>Name:</dt> <dd>srhSegmentIPv6EndpointBehavior</dd></dl> <dl> <dt>ElementID:</dt> <dd>TBD11</dd> </dl> <dl><dt>Abstract Data Type:</dt> <dd>unsigned16</dd> <dt>Data Type Semantics:</dt> <dd>identifier</dd> <dt>Description:</dt> <dd>The 16-bit unsigned integer that representsaan SRv6 Endpoint behavior as perSection 4 of<xreftarget="RFC8986"/>.target="RFC8986" sectionFormat="of" section="4"/>. Assigned values and their meanings are provided in the"SRV6"SRv6 EndpointBehavior"Behaviors" registry.</dd></dl> <dl> <dt>Abstract Data Type:</dt> <dd>unsigned16</dd> </dl> <dl> <dt>Data Type Semantics:</dt> <dd>identifier</dd> </dl> <dl><dt>Additional Information:</dt> <dd>See the assigned behaviorsatin the "SRv6 EndpointBehavior"Behaviors" registryavailableathttps://www.iana.org/assignments/segment-routing/segment-routing.xhtml#srv6-endpoint-behaviors.<eref target="https://www.iana.org/assignments/segment-routing" brackets="angle"/>. SeeSection 4 of<xreftarget="RFC8986"/>target="RFC8986" sectionFormat="of" section="4"/> for more details about the processing of endpointbehaviors processing.</dd> </dl> <dl>behaviors.</dd> <dt>Reference:</dt><dd>[RFC-to-be]</dd><dd>RFC 9487</dd> </dl> </section> </section> <section anchor="IPFIXIPv6SRHSegmentTypeSubregistry"title="Newnumbered="true" toc="default"> <name>New IPFIX IPv6 SRH Segment TypeSubregistry"> <t>This document requests IANA to create(Value 500) Subregistry</name> <t>IANA has created a new subregistry called "IPFIX IPv6 SRH SegmentType"Type (Value 500)" under the "IPFIX Information Elements" registry <xreftarget="RFC7012"/> availabletarget="RFC7012" format="default"/> at <xreftarget="IANA-IPFIX"/>.</t>target="IANA-IPFIX" format="default"/>.</t> <t>The allocation policy of this new subregistry is Expert Review(Section 4.5 of <xref target="RFC8126"/>).</t>(<xref target="RFC8126" sectionFormat="of" section="4.5"/>).</t> <t>The designated experts for this registry should be familiar with SRH. The guidelines that are being followed by the designated experts for theIPFIX"IPFIX Information Elements" registry should be followed for this subregistry. In particular, criteria that should be applied by the designated experts include determining whether the proposed registration duplicates existing entries and whether the registration description is clear and fits the purpose of this registry. Within the review period, the designated experts will either approve or deny the registration request, communicating this decision to IANA. Denials should include an explanation and, if applicable, suggestions as to how to make the request successful.</t> <t>Initial values in the registry are defined inTable 2.</t> <t><figure> <artwork><![CDATA[ +-------+--------------------+---------------------------------------+ | Value | Description | Additional Information | +-------+--------------------+---------------------------------------+ | TBD12 | Unknown | [RFC-to-be] | | | | | +-------+--------------------+---------------------------------------+ | TBD13 | Segment Routing | [RFC-to-be], | | | Policy |<xreftarget="RFC9256"/> | +-------+--------------------+---------------------------------------+ | TBD14 | Path Computation | [RFC-to-be],<xref target=" | | | Element | I-D.ietf-pce-segment-routing-ipv6"/> | +-------+--------------------+---------------------------------------+ | TBD15 | OSPFv3 | [RFC-to-be],<xref target=" | | | Segment Routing | I-D.ietf-lsr-ospfv3-srv6-extensions"/>| +-------+--------------------+---------------------------------------+ | TBD16 | IS-IS | [RFC-to-be],<xref target="RFC9352"/> | | |target="table2"/>.</t> <table anchor="table2" align="center"> <name>IPFIX IPv6 SRH Segment Type (Value 500) Subregistry</name> <thead> <tr> <th>Value</th> <th>Description</th> <th>Reference</th> </tr> </thead> <tbody> <tr> <td>0</td> <td>Unknown</td> <td>RFC 9487</td> </tr> <tr> <td>1</td> <td>Segment Routing| | +-------+--------------------+---------------------------------------+ | TBD17 | BGPPolicy</td> <td>RFC 9487, <xref target="RFC9256"/></td> </tr> <tr> <td>2</td> <td>Path Computation Element</td> <td>RFC 9487, <xref target="I-D.ietf-pce-segment-routing-ipv6"/></td> </tr> <tr> <td>3</td> <td>OSPFv3 Segment Routing</td> <td>RFC 9487, <xref target="I-D.ietf-lsr-ospfv3-srv6-extensions"/></td> </tr> <tr> <td>4</td> <td>IS-IS Segment Routing</td> <td>RFC 9487, <xref target="RFC9352"/></td> </tr> <tr> <td>5</td> <td>BGP Segment| [RFC-to-be], | | |RoutingPrefix-SID | <xref target="RFC8669"/> | +-------+--------------------+---------------------------------------+ Table 2: "IPFIX IPv6 SRH Segment Type" Subregistry ]]></artwork> </figure></t>Prefix-SID</td> <td>RFC 9487, <xref target="RFC8669"/></td> </tr> </tbody> </table> </section> </section> <section anchor="Operational"title="Operational Considerations">numbered="true" toc="default"> <name>Operational Considerations</name> <section anchor="OpsSidList"title="SRv6numbered="true" toc="default"> <name>SRv6 SegmentList">List</name> <t>The zero or more 128-bit IPv6 addresses in the SRH[RFC8754]<xref target="RFC8754" format="default"/> can be exported in two different ways, with two different IPFIX IEs:</t><t><list style="symbols"> <t>srhSegmentIPv6BasicList</t> <t>srhSegmentIPv6ListSection</t> </list></t><ul spacing="normal"> <li>srhSegmentIPv6BasicList</li> <li>srhSegmentIPv6ListSection</li> </ul> <t>The srhSegmentIPv6BasicList encodes the SRv6 Segment List with a basicList, specified in the IPFIX Structured Data <xreftarget="RFC6313"/>.target="RFC6313" format="default"/>. This encodingoffers theis an advantageto thefor data collectionthatsince the different IPv6 addresses are already structured as a list, without the need of post-processing. However, this method requires some extra processing on theexporter,exporter to realize theBasicListbasicList data mapping.</t> <t>The srhSegmentIPv6ListSection, on the other hand, encodes the list of IPv6 addresses as an octetArray. This doesn't impose any data flow manipulation on the exporter, facilitating the immediate export. However, the data collectionMUST<bcp14>MUST</bcp14> be able to decode the IPv6 addresses according to the SR specifications. Compared to the srhSegmentIPv6BasicList, the srhSegmentIPv6ListSection flow records length is slightly reduced.</t> <t>It is not expected that an exporter would support both srhSegmentIPv6BasicList and srhSegmentIPv6ListSection at the same time.</t> </section> <section anchor="OpsSidListDecompose"title="Compressednumbered="true" toc="default"> <name>Compressed SRv6 Segment ListDecomposition">Decomposition</name> <t>The SRv6 Segment List in the IPFIX IEs srhSegmentIPv6BasicList,srhSegmentIPv6ListSectionsrhSegmentIPv6ListSection, and destinationIPv6Address could contain compressed-SID containers as described in <xreftarget="I-D.ietf-spring-srv6-srh-compression"/>.target="I-D.ietf-spring-srv6-srh-compression" format="default"/>. The SR Endpoint Flavors, as described in Section 4 of <xreftarget="I-D.ietf-spring-srv6-srh-compression"/> definestarget="I-D.ietf-spring-srv6-srh-compression" format="default"/>, define new flavors for SIDendpoint behaviors,Endpoint behaviors and determine wherever the Segment List encoding is compressed, along with the flavor. The SIDLocatorLocator, as described inSection 3.1 of<xreftarget="RFC8986"/>,target="RFC8986" sectionFormat="of" section="3.1"/>, determines the common most significant bits. By using described information from srhSegmentIPv6EndpointBehavior andsrhSegmentIPv6LocatorLengthsrhSegmentIPv6LocatorLength, the compressed-SID containers can be decoded at the data collection.</t> </section> </section> <sectionanchor="Acknowledgements" title="Acknowledgements"> <t>The authors would like to thank Yao Liu, Eduard Vasilenko, Bruno Decraene, Mohamed Boucadair, Kamran Raza, Qin Wu, Jim Guichard, Tero Kivinen, Paul Aitken, Roman Danyliw, John Scudder, Eric Vyncke, Erik Kline, Lars Eggert and Andrew Alston for their review and valuable comments, and Paolo Lucente and Alex Huang Feng for the implementation and validation.</t> </section> <section anchor="Implementation" title="Implementation Status"> <t>Note to the RFC-Editor: Please remove this section before publishing.</t> <section anchor="VPP" title="FD.io VPP"> <t>INSA Lyon implemented the following IEs as part of a prototype in the FD.io VPP (Vector Packet Processing) platform:</t> <t><list style="symbols"> <t>srhActiveSegmentIPv6</t> <t>srhSegmentIPv6EndpointBehavior</t> <t>srhSegmentsIPv6Left</t> <t>srhFlagsIPv6</t> <t>srhTagIPv6</t> <t>srhSegmentIPv6ListSection</t> <t>srhSegmentIPv6BasicList</t> </list></t> <t>The open source code can be obtained here: <xref target="INSA-Lyon-VPP"/> and was validated at the IETF 115 hackathon.</t> </section> <section anchor="Huawei" title="Huawei VRP"> <t>Huawei implemented the following IEs as part of a production implementation in the VRP platform:</t> <t><list style="symbols"> <t>srhActiveSegmentIPv6</t> <t>srhSegmentsIPv6Left</t> <t>srhFlagsIPv6</t> <t>srhTagIPv6</t> <t>srhSegmentIPv6ListSection</t> </list></t> <t>The implementation was validated at the IETF 115 hackathon.</t> </section> <section anchor="pmacct" title="Pmacct Data Collection"> <t>Paolo Lucente implemented the decomposition of the IE srhSegmentIPv6ListSection as part of a a production implementation in the open source Network Telemetry data collection project pmacct.</t> <t>The source code can be obtained here: <xref target="Paolo-Lucente-Pmacct"/> and was validated at the IETF 115 hackathon.</t> </section> </section> <sectionanchor="Security"title="Security Considerations">numbered="true" toc="default"> <name>Security Considerations</name> <t>Thereexistsare noextraadditional security considerations regarding allocation of these new IPFIX IEs compared to <xreftarget="RFC7012"/>.</t>target="RFC7012" format="default"/>.</t> <t>The IEs described in this document export provider plane data metrics on how packets are being forwarded withinaan SRv6 network. Applications and operators using the IEs described in this document must evaluate the sensitivity of this information in their implementationcontext,context and apply the data-at-rest storage guidance inSection 11.8 of<xreftarget="RFC7011"/>target="RFC7011" sectionFormat="of" section="11.8"/> as appropriate.</t> </section> </middle> <back><references title="Normative References"> <?rfc include='reference.RFC.2119'?> <?rfc include='reference.RFC.6313'?> <?rfc include='reference.RFC.7011'?> <?rfc include='reference.RFC.7012'?> <?rfc include='reference.RFC.8126'?> <?rfc include='reference.RFC.8174'?> <?rfc include='reference.RFC.8200'?> <?rfc include='reference.RFC.8754'?><displayreference target="I-D.ietf-lsr-ospfv3-srv6-extensions" to="OSPFV3-SRV6-EXT"/> <displayreference target="I-D.ietf-pce-segment-routing-ipv6" to="PCEP-SRV6-EXT"/> <displayreference target="I-D.ietf-spring-srv6-srh-compression" to="SRV6-SRH-COM"/> <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.6313.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.7011.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.7012.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8126.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.8200.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8754.xml"/> </references><references title="Informative References"> <?rfc include='reference.RFC.7270'?> <?rfc include='reference.RFC.8402'?> <?rfc include='reference.RFC.8669'?> <?rfc include='reference.RFC.8986'?> <?rfc include='reference.RFC.9256'?> <?rfc include='reference.RFC.9352'?> <?rfc include='reference.I-D.ietf-lsr-ospfv3-srv6-extensions'?> <?rfc include='reference.I-D.ietf-pce-segment-routing-ipv6'?> <?rfc include='reference.I-D.ietf-spring-srv6-srh-compression'?><references> <name>Informative References</name> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.7270.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8402.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8669.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8986.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.9256.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.9352.xml"/> <!-- [I-D.ietf-lsr-ospfv3-srv6-extensions] In AUTH48 state as of 11/6/23. Updated to long version because missing editor role.--> <referenceanchor="IANA-IPFIX" target="https://www.iana.org/assignments/ipfix/ipfix.xhtml">anchor="I-D.ietf-lsr-ospfv3-srv6-extensions"> <front><title>IANA, "IP Flow Information Export (IPFIX) Entities"</title> <author/> <date/><title>OSPFv3 Extensions for SRv6</title> <author initials="Z." surname="Li" fullname="Zhenbin Li"> <organization>Huawei Technologies</organization> </author> <author initials="Z." surname="Hu" fullname="Zhibo Hu"> <organization>Huawei Technologies</organization> </author> <author initials="K." surname="Talaulikar" fullname="Ketan Talaulikar" role="editor"> <organization>Cisco Systems</organization> </author> <author initials="P." surname="Psenak" fullname="Peter Psenak"> <organization>Cisco Systems</organization> </author> <date month="June" day="21" year="2023"/> </front> <seriesInfo name="Internet-Draft" value="draft-ietf-lsr-ospfv3-srv6-extensions-15"/> </reference> <!-- [I-D.ietf-pce-segment-routing-ipv6] IESG state: publication requested as of 11/6/23 --> <xi:include href="https://bib.ietf.org/public/rfc/bibxml3/reference.I-D.ietf-pce-segment-routing-ipv6"/> <!-- [I-D.ietf-spring-srv6-srh-compression] IESG state: I-D Exists as of 11/6/23. Updated to long version because missing editor role--> <referenceanchor="INSA-Lyon-VPP" target="https://github.com/network-analytics/vpp-srh-onpath-telemetry">anchor="I-D.ietf-spring-srv6-srh-compression"> <front><title>INSA Lyon, FD.io VPP implementation</title> <author/> <date/><title>Compressed SRv6 Segment List Encoding</title> <author initials="W." surname="Cheng" fullname="Weiqiang Cheng" role="editor"> <organization>China Mobile</organization> </author> <author initials="C." surname="Filsfils" fullname="Clarence Filsfils"> <organization>Cisco Systems, Inc.</organization> </author> <author initials="Z." surname="Li" fullname="Zhenbin Li"> <organization>Huawei Technologies</organization> </author> <author initials="B." surname="Decraene" fullname="Bruno Decraene"> <organization>Orange</organization> </author> <author initials="F." surname="Clad" fullname="Francois Clad" role="editor"> <organization>Cisco Systems, Inc.</organization> </author> <date month="October" day="23" year="2023"/> </front> <seriesInfo name="Internet-Draft" value="draft-ietf-spring-srv6-srh-compression-09"/> </reference> <referenceanchor="Paolo-Lucente-Pmacct" target="https://github.com/pmacct/pmacct">anchor="IANA-IPFIX" target="https://www.iana.org/assignments/ipfix"> <front><title>Paolo Lucente, Pmacct open source Network Telemetry Data Collection</title> <author/><title>IP Flow Information Export (IPFIX) Entities</title> <author> <organization>IANA</organization> </author> <date/> </front> </reference> </references> </references> <section anchor="Encoding-Example"title="IPFIXnumbered="true" toc="default"> <name>IPFIX EncodingExamples">Examples</name> <t>This appendix represents three different encodings for the newly introduced IEs, for the example values inTable 3.<xref target="table3"/>. The three different encodings use the following IEs, respectively: srhSegmentIPv6BasicList, srhSegmentIPv6ListSection, and srhIPv6Section.</t><t><figure> <artwork><![CDATA[ +-----+------+-----+----------------+--------------------------| | SRH | SRH | SRH | Active Segment | Segment List | | Nr | Flags| Tag | Type | | +-----+------+-----+----------------+--------------------------+ | 1 | 0 | 123 | IS-IS | 2001:db8::1, 2001:db8::2,| | | | | | 2001:db8::3 | +-----+------+-----+----------------+--------------------------+ | 2 | 0 | 456 | IS-IS | 2001:db8::4, 2001:db8::5 | +-----+------+-----+----------------+--------------------------+ | 3 | 0 | 789 | IS-IS | 2001:db8::6 | +-----+------+-----+----------------+--------------------------+ Table 3: Three<table anchor="table3" align="center"> <name>Three Observed SRHheadersHeaders and Their Associated RoutingProtocol ]]></artwork> </figure></t>Protocols</name> <thead> <tr> <th>SRH Nr</th> <th>SRH Flags</th> <th>SRH Tag</th> <th>Active Segment Type</th> <th>Segment List</th> </tr> </thead> <tbody> <tr> <td>1</td> <td>0</td> <td>123</td> <td>IS-IS [4]</td> <td>2001:db8::1, 2001:db8::2, 2001:db8::3</td> </tr> <tr> <td>2</td> <td>0</td> <td>456</td> <td>IS-IS [4]</td> <td>2001:db8::4, 2001:db8::5</td> </tr> <tr> <td>3</td> <td>0</td> <td>789</td> <td>IS-IS [4]</td> <td>2001:db8::6</td> </tr> </tbody> </table> <section anchor="Three-Observed-SRH-Headers-and-their-routing-protocol"title="Threenumbered="true" toc="default"> <name>Three Observed SRH Headers andtheirTheir RoutingProtocol">Protocols</name> <section anchor="Template-Record-and-Data-Set-with-BasicList"title="Templatenumbered="true" toc="default"> <name>Template Record and Data Set with Segment BasicList">List</name> <t>With encoding inFigure 1,<xref target="fig1"/>, the examples inTable 3<xref target="table3"/> are represented with the followingIEs: “=>”IEs, where "=>" is used to indicate which IE is mapped toagiveninformation.</t> <t><list style="symbols"> <t>SRinformation:</t> <ul spacing="normal"> <li>SRH Flags => srhFlagsIPv6(TBD1)</t> <t>SR(492)</li> <li>SRH Tag => srhTagIPv6(TBD2)</t> <t>Active(493)</li> <li>Active Segment Type => srhIPv6ActiveSegmentType(TBD9)</t> <t>Segment(500)</li> <li>Segment List => srhSegmentIPv6BasicList(TBD5)</t> </list></t> <t><figure> <artwork><![CDATA[(496)</li> </ul> <figure anchor="fig1" align="center"> <name>Template Record with Basic List Encoding Format</name> <artwork name="" type="" align="center" alt=""><![CDATA[ 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SET ID = 2 | Length = 24 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Template ID = 256 | Field Count = 4 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| srhFlagsIPv6 =TBD1492 | Field Length = 1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| srhTagIPv6 =TBD2493 | Field Length = 2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+|0|srhActiveSegmentIPv... = TBD9||0|srhIPv6ActiveSegmentType= 500| Field Length = 1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+|0|srhSegmentIPv6BasicList= TBD5||0|srhSegmentIPv6BasicList = 496| Field Length = 0xFFFF | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+Figure 1: Template Record with Basic List Encoding Format]]></artwork></figure></t></figure> <t>In this example, the Template ID is 256, which will be used in the Data Record. The field length for srhSegmentIPv6BasicList is 0xFFFF, which means the length of this IE is variable, and the actual length of this IE is indicated by the List Length field in the basicList format as per <xreftarget="RFC6313"/>.</t>target="RFC6313" format="default"/>.</t> <t>The data set is represented as follows:</t><figure> <artwork><![CDATA[<figure anchor="fig2" align="center"> <name>Data Set Encoding Format for Basic List</name> <artwork name="" type="" align="center" alt=""><![CDATA[ 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SET ID = 256 | Length = 136 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhFlagsIPv6 | srhTagIPv6 = 123 |srhIPv6Active |srhActiveSegme|| = 0 || ntIPv...=TBD16||SegmentType= 4| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 255 | List Length = 53 |semantic= | | | |ordered | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhSegmentIPv6 =TBD3494 | Field Length = 16 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[0] = 2001:db8::1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[1] = 2001:db8::2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[2] = 2001:db8::3 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhFlagsIPv6 | srhTagIPv6 = 456 |srhActiveSegme|srhIPv6Active | | = 0 | |ntIPv...=TBD16|SegmentType= 4| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 255 | List Length = 37 |semantic= | | | |ordered | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhSegmentIPv6 =TBD3494 | Field Length = 16 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[0] = 2001:db8::4 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[1] = 2001:db8::5 (16 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhFlagsIPv6 | srhTagIPv6 = 789 |srhActiveSegme|srhIPv6Active | | = 0 | |ntIPv...=TBD16|SegmentType= 4| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 255 | List Length = 21 |semantic= | | | |ordered | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhSegmentIPv6 =TBD3494 | Field Length = 16 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[0] = 2001:db8::6 ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+Figure 2: Data Set Encoding Format for Basic List]]></artwork> </figure> </section> <section anchor="Template-Record-and-Data-Set-with-Segment-List-Section"title="Templatenumbered="true" toc="default"> <name>Template Record and Data Set with Segment ListSection">Section</name> <t>With encoding inFigure 3,<xref target="fig3"/>, the examples inTable 3<xref target="table3"/> are represented with the followingIEs: “=>”IEs, where "=>" is used to indicate which IE is mapped toagiveninformation.</t> <t><list style="symbols"> <t>SRinformation:</t> <ul spacing="normal"> <li>SRH Flags => srhFlagsIPv6(TBD1)</t> <t>SR(492)</li> <li>SRH Tag => srhTagIPv6(TBD2)</t> <t>Active(493)</li> <li>Active Segment Type => srhIPv6ActiveSegmentType(TBD9)</t> <t>Segment(500)</li> <li>Segment List => srhSegmentIPv6ListSection(TBD6)</t> </list></t> <t><figure> <artwork><![CDATA[(497)</li> </ul> <figure align="center" anchor="fig3"> <name>Template Record with Segment List Section Encoding Format</name> <artwork name="" type="" align="center" alt=""><![CDATA[ 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SET ID = 2 | Length = 24 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Template ID = 257 | Field Count = 4 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| srhFlagsIPv6 =TBD1492 | Field Length = 1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| srhTagIPv6 =TBD2493 | Field Length = 2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+|0|srhActiveSegmentIPv... = TBD9||0|srhIPv6ActiveSegmentType= 500| Field Length = 1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+|0| srhSegmentIPv6List ||0|srhSegmentIPv6ListSection=497| Field Length = 0xFFFF || | Section=TBD6 | |+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+Figure 3: Template Record with Segment List Section Encoding Format]]></artwork></figure></t></figure> <t>In this example, the Template ID is 257, which will be used in the Data Record. The field length for srhSegmentIPv6ListSection in the Template Record is 0xFFFF, which means that the length of this IE is variable: its actual length is encoded in the Data Set. Note that, with an actual length inferior to 255 in the Data Record example, the length field is encoded in 8 bits(Section 7 of <xref target="RFC7011"/>).</t>(<xref target="RFC7011" sectionFormat="of" section="7"/>).</t> <t>The data can be represented as follows:</t><figure> <artwork><![CDATA[<figure align="center" anchor="fig4"> <name>Data Set Encoding Format for Segment List Section</name> <artwork name="" type="" align="center" alt=""><![CDATA[ 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SET ID = 257 | Length = 116 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhFlagsIPv6 | srhTagIPv6 = 123 |srhActiveSegme|srhIPv6Active | | = 0 | |ntIPv...=TBD16|SegmentType= 4| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Length = 48 | 2001:db8::1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | 2001:db8::2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | 2001:db8::3 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | srhFlagsIPv6 | srhTagIPv6 = 456 | | | = 0 | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |srhActiveSegme|srhIPv6Active | Length = 32 | 2001:db8::4 | |ntIPv...=TBD15|SegmentType= 4| | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | 2001:db8::5 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... |srhFlagsIPv6=0 |srhTagIPv6...srhTagIPv6 = | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |=789 |srhActiveSegmentsrhIPv6ActiveSegmentType = 4 | Length = 16 | | |IPv6Type=TBD16| | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 2001:db8::6 ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+Figure 4: Data Set Encoding Format for Segment List Section]]></artwork> </figure> </section> <section anchor="Template-Record-and-Data-Set-with-SRH-Section"title="Templatenumbered="true" toc="default"> <name>Template Record and Data Set with SRHSection">Section</name> <t>With encoding inFigure 5,<xref target="fig5"/>, the examples inTable 3<xref target="table3"/> are represented with the followingIEs: “=>”IEs, where "=>" is used to indicate which IE is mapped toagiveninformation.</t> <t><list style="symbols"> <t>SRinformation:</t> <ul spacing="normal"> <li>SRH Flags +SRSRH Tag + Segment List => srhIPv6Section(TBD8)</t> <t>Active(499)</li> <li>Active Segment Type => srhIPv6ActiveSegmentType(TBD9)</t> </list></t> <t><figure> <artwork><![CDATA[(500)</li> </ul> <figure anchor="fig5" align="center"> <name>Template Record with SRH Section Encoding Format</name> <artwork name="" type="" align="center" alt=""><![CDATA[ 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SET ID = 2 | Length = 16 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Template ID = 258 | Field Count = 2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+|0| srhActiveSegmentIP... = TBD9||0|srhIPv6ActiveSegmentType= 500| Field Length = 1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| srhIPv6Section =TBD8499 | Field Length = 0xFFFF | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+Figure 5: Template Record with SRH Section Encoding Format]]></artwork></figure></t></figure> <t>In this example, the Template ID is 258, which will be used in the Data Record. The field length for srhIPv6Section in the Template Record is 0xFFFF, which means that the length of this IE is variable: its actual length is encoded in the Data Set. Note that, with an actual length inferior to 255 in the Data Record example, the length field is encoded in 8 bits(Section 7 of <xref target="RFC7011"/>).</t>(<xref target="RFC7011" sectionFormat="of" section="7"/>).</t> <t>The data can be represented as follows:</t><figure> <artwork><![CDATA[<figure anchor="fig6" align="center"> <name>Data Set Encoding Format for SRH Section</name> <artwork name="" type="" align="center" alt=""><![CDATA[ 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SET ID = 258 | Length = (*) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhIPv6ActiveSegmentType =TBD164 | Length = (*) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Next Header | Hdr Ext Len | Routing Type | Segments Left | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Last Entry | Flags | Tag | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Segment List[0]2001:db8::1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Segment List[1]2001:db8::2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Segment List[2]2001:db8::3 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Optional Type Length Value objects (variable) ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhIPv6ActiveSegmentType =TBD164 | 0xFFFF | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Next Header | Hdr Ext Len | Routing Type | Segments Left | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Last Entry | Flags | Tag | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Segment List[0]2001:db8::4 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Segment List[1]2001:db8::5 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Optional Type Length Value objects (variable) ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhIPv6ActiveSegmentType =TBD164 | 0xFFFF | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Next Header | Hdr Ext Len | Routing Type | Segments Left | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Last Entry | Flags | Tag | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Segment List[0]2001:db8::6 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Optional Type Length Value objects (variable) ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+Figure 6: Data Set Encoding Format for SRH Section]]></artwork> </figure> <t>(*) The Length must be calculated to include the optional Type Length Value objects.</t> </section> </section> <section anchor="Options-Template-Record-and-Data-Set-for-SRv6-Segment-Endpoint-Behavior"title="Optionsnumbered="true" toc="default"> <name>Options Template Record and Data Set for SRv6 SegmentEnd Point behaviorEndpoint Behavior and LocatorLength">Length</name> <t>This appendix provides an SRv6EndPoint BevahiorEndpoint Behavior Options Template example, for the values presented inTable 4.<xref target="table4"/>. In the Options Template case, the srhActiveSegmentIPv6Information ElementIE is a Scopefield</t> <t><figure> <artwork><![CDATA[ +-------+-------------+-------------------------+----------------+ | Entry | SRH End | SRH End | SRHfield.</t> <table anchor="table4" align="center"> <name>Three Observed SRv6 Segment Endpoint Behaviors</name> <thead> <tr> <th>Entry Nr</th> <th>SRH Endpoint IPv6</th> <th>SRH Endpoint Behavior</th> <th>SRH Segment| | Nr | Point IPv6 | Point Behavior |LocatorLength | +-------+-------------+-------------------------+----------------+ | 1 | 2001:db8::1 | End [1] | 48 | +-------+-------------+-------------------------+----------------+ | 2 | 2001:db8::4 | EndLength</th> </tr> </thead> <tbody> <tr> <td>1</td> <td>2001:db8::1</td> <td>End [1]</td> <td>48</td> </tr> <tr> <td>2</td> <td>2001:db8::4</td> <td>End with NEXT-CSID[43] | 48 | +-------+-------------+-------------------------+----------------+ | 3 | 2001:db8::6 | End.DX6 [16] | 48 | +-------+-------------+-------------------------+----------------+ Table 4: Three Observed SRv6 Segment End Point Behaviors ]]></artwork> </figure></t> <t><figure> <artwork><![CDATA[[43]</td> <td>48</td> </tr> <tr> <td>3</td> <td>2001:db8::6</td> <td>End.DX6 [16]</td> <td>48</td> </tr> </tbody> </table> <figure anchor="fig7" align="center"> <name>Segment Endpoint Behavior Options Template Record</name> <artwork name="" type="" align="center" alt=""><![CDATA[ 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Set ID = 3 | Length = 24 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Template ID 259 | Field Count = 3 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Scope Field Count = 1 |0| srhActiveSegmentIPv6 =TBD4495 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Scope 1 Field Length = 4|0|srhSegmentEndpointBeh..=TBD11||0|srhSegmentIPv6End.Behav = 502| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Field Length = 1|0|srhSegmentIPv6Lo.Length=TBD10||0|srhSegmentIPv6Lo.Length = 501| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Field Length = 4 | Padding | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+Figure 7: Template Record with SRH Section Encoding Format]]></artwork></figure></t></figure> <t>In this example, the Template ID is 259, which will be used in the Data Record.</t> <t>The data set is represented as follows:</t><figure> <artwork><![CDATA[<figure anchor="fig8" align="center"> <name>Data Set Encoding Format for Segment Endpoint Behaviors</name> <artwork name="" type="" align="center" alt=""><![CDATA[ 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SET ID = 259 | Length = 28 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhActiveSegmentIPv6 = 2001:db8::1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+||srhSegmentIPv6EndpointBehavior |srhSegmentIPv6LocatorLength= 48| |= End [1] |48| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhActiveSegmentIPv6 = 2001:db8::4 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+||srhSegmentIPv6EndpointBehavior |srhSegmentIPv6LocatorLength= 48| |= End with NEXT-CSID [43] |48| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhActiveSegmentIPv6 = 2001:db8::6 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+||srhSegmentIPv6EndpointBehavior |srhSegmentIPv6LocatorLength= 48| |= End.DX6 [16] |48| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+Figure 8: Data Set Encoding Format for SRH Section]]></artwork> </figure> <t>(*) The Length must be calculated to include the optional Type Length Value objects.</t> </section> </section> <section anchor="Acknowledgements" numbered="false" toc="default"> <name>Acknowledgements</name> <t>The authors would like to thank <contact fullname="Yao Liu"/>, <contact fullname="Eduard Vasilenko"/>, <contact fullname="Bruno Decraene"/>, <contact fullname="Mohamed Boucadair"/>, <contact fullname="Kamran Raza"/>, <contact fullname="Qin Wu"/>, <contact fullname="Jim Guichard"/>, <contact fullname="Tero Kivinen"/>, <contact fullname="Paul Aitken"/>, <contact fullname="Roman Danyliw"/>, <contact fullname="John Scudder"/>, <contact fullname="Éric Vyncke"/>, <contact fullname="Erik Kline"/>, <contact fullname="Lars Eggert"/>, and <contact fullname="Andrew Alston"/> for their reviews and valuable comments. And thank you to <contact fullname="Paolo Lucente"/> and <contact fullname="Alex Huang Feng"/> for the implementation and validation.</t> </section> </back> </rfc>