rfc9974.original.xml   rfc9974.xml 
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<front>
<title abbrev="OAM Requirements for BIER">Operations, Administration and
Maintenance (OAM) Requirements for Bit Index Explicit Replication (BIER) Layer</
title>
<author initials="G." surname="Mirsky" fullname="Greg Mirsky" role="edito
r">
<organization>Ericsson</organization>
<address>
<email>gregimirsky@gmail.com</email>
</address>
</author>
<author initials="N." surname="Kumar" fullname="Nagendra Kumar"> <rfc xmlns:xi="http://www.w3.org/2001/XInclude" category="info" ipr="trust200902
<organization>Oracle</organization> " docName="draft-ietf-bier-oam-requirements-21" number="9974" consensus="true" o
<address> bsoletes="" updates="" submissionType="IETF" xml:lang="en" tocInclude="true" toc
<email>nagendrakumar.nainar@gmail.com</email> Depth="3" symRefs="true" sortRefs="true" version="3">
</address>
</author>
<author initials="M." surname="Chen" fullname="Mach Chen">
<organization>Huawei Technologies</organization>
<address>
<email>mach.chen@huawei.com</email>
</address>
</author>
<author initials="S" surname="Pallagatti" fullname="Santosh Pallagatti" r <front>
ole="editor"> <title abbrev="OAM Requirements for BIER">Operations, Administration, and Ma
<organization>VMware</organization> intenance (OAM) Requirements for the Bit Index Explicit Replication (BIER) Layer
<address> </title>
<email>santosh.pallagatti@gmail.com</email> <seriesInfo name="RFC" value="9974"/>
</address> <author initials="G." surname="Mirsky" fullname="Greg Mirsky" role="editor">
</author> <organization>Ericsson</organization>
<address>
<email>gregimirsky@gmail.com</email>
</address>
</author>
<date year="2025"/> <author initials="N." surname="Kumar" fullname="Nagendra Kumar">
<organization>Oracle</organization>
<address>
<email>nagendrakumar.nainar@gmail.com</email>
</address>
</author>
<area>Routing</area> <author initials="M." surname="Chen" fullname="Mach Chen">
<organization>Huawei Technologies</organization>
<address>
<email>mach.chen@huawei.com</email>
</address>
</author>
<workgroup>BIER Working Group</workgroup> <author initials="S" surname="Pallagatti" fullname="Santosh Pallagatti" role
="editor">
<organization>VMware</organization>
<address>
<email>santosh.pallagatti@gmail.com</email>
</address>
</author>
<keyword>Internet-Draft</keyword> <date month="May" year="2026"/>
<keyword>BIER</keyword> <area>RTG</area>
<workgroup>bier</workgroup>
<keyword>OAM</keyword> <keyword>BIER</keyword>
<keyword>OAM</keyword>
<abstract> <abstract>
<t> <t>
This document specifies a list of functional requirements for Operatio ns, Administration, and Maintenance This document specifies a list of functional requirements for Operatio ns, Administration, and Maintenance
mechanisms, protocols, and tools that support operations in the Bit In dex Explicit Replication layer of a network. mechanisms, protocols, and tools that support operations in the Bit In dex Explicit Replication layer of a network.
</t> </t>
</abstract> </abstract>
</front> </front>
<middle> <middle>
<section anchor="intro" title="Introduction"> <section anchor="intro">
<name>Introduction</name>
<t> <t>
<xref target="RFC8279"/> specifies a Bit Index Explicit Replication (BIER) <xref target="RFC8279"/> specifies a Bit Index Explicit Replication (BIER)
architecture and how it supports forwarding of multicast data packets. architecture and how it supports forwarding of multicast data packets.
</t> </t>
<t> <t>
This document lists the Operations, Administration, and Maintenance (OAM) req uirements for the BIER layer This document lists the Operations, Administration, and Maintenance (OAM) req uirements for the BIER layer
(Section 4.2 of <xref target="RFC8279"/>) of the multicast domain. (see <xref target="RFC8279" section="4.2"/>) of the multicast domain.
The list can further be used for gap analysis of available OAM tools to ident ify The list can further be used for gap analysis of available OAM tools to ident ify
possible enhancements of existing or whether new OAM tools are required to whether possible enhancements of existing or new OAM tools are required to
support proactive and on-demand path monitoring and service validation. support proactive and on-demand path monitoring and service validation.
</t> </t>
<section title="Conventions used in this document"> <section>
<section anchor="term-sec" title="Terminology"> <name>Conventions Used in This Document</name>
<section anchor="term-sec">
<name>Terminology</name>
<t>The reader is expected to be familiar with:</t> <t>The reader is expected to be familiar with:</t>
<ul spacing="normal"> <ul spacing="normal">
<li><xref target="RFC7799"/>, particularly definitions of Active, Passive, and H ybrid measurement methods and metrics.</li> <li><xref target="RFC7799"/>, particularly definitions of Active, Passive, and H ybrid measurement methods and metrics.</li>
<li>The definitions and calculation of performance metrics, e.g., throughput, lo ss, delay, and delay variation metrics, are defined in <xref target="RFC6374"/>. </li> <li>The definitions and calculation of performance metrics, e.g., throughput, lo ss, delay, and delay variation metrics, are defined in <xref target="RFC6374"/>. </li>
<li>The definitions, applicability, and examples of the Continuity Check and Con nectivity Verification mechanisms, components of the Fault Management OAM, <li>The definitions, applicability, and examples of the Continuity Check and Con nectivity Verification mechanisms, components of the Fault Management OAM,
can be found in <xref target="RFC5860"/>,<xref target="RFC6371"/>, and <xref ta can be found in <xref target="RFC5860"/>, <xref target="RFC6371"/>, and <xref t
rget="RFC7276"/>.</li> arget="RFC7276"/>.</li>
<li>A multicast domain is a network segment that defines the scope for the multi <li>A multicast domain is a network segment that defines the scope for multicast
cast traffic, allowing it to be exchanged only among systems within the domain < traffic, allowing it to be exchanged only among systems within the domain <xref
xref target="RFC8279"/>.</li> target="RFC8279"/>.</li>
<li>The term "BIER OAM" is used in this document interchangeably with "a set of OAM protocols, methods, and tools for the BIER layer".</li> <li>The term "BIER OAM" is used in this document interchangeably with "a set of OAM protocols, methods, and tools for the BIER layer".</li>
<li>Downstream - is the direction from the ingress toward the egress endpoints o f a multicast distribution tree.</li> <li>Downstream is the direction from the ingress toward the egress endpoints of a multicast distribution tree.</li>
<li>Egress endpoint is a router to which the packet needs to be sent <xref targe t="RFC8279"/>.</li> <li>Egress endpoint is a router to which the packet needs to be sent <xref targe t="RFC8279"/>.</li>
<li>Ingress endpoint is a router that encapsulates a packet in a BIER header <xr ef target="RFC8279"/>.</li> <li>Ingress endpoint is a router that encapsulates a packet in a BIER header <xr ef target="RFC8279"/>.</li>
<li> <li>
A BIER OAM session is a communication established between Bit-Forwarding Rout ers (BFR) to perform OAM A BIER OAM session is a communication established between Bit-Forwarding Rout ers (BFR) to perform OAM
functions like fault detection, performance monitoring, and localization <xre f target="RFC7276"/>. functions like fault detection, performance monitoring, and localization <xre f target="RFC7276"/>.
These sessions can be proactive (continuous, persistent configuration) or on- demand (manual, temporary diagnostics). These sessions can be proactive (continuous, persistent configuration) or on- demand (manual, temporary diagnostics).
</li> </li>
</ul> </ul>
</section> </section>
<section title="Requirements Language"> <section>
<name>Requirements Language</name>
<t> <t>
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL The key words "<bcp14>MUST</bcp14>", "<bcp14>MUST NOT</bcp14>",
NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "<bcp14>REQUIRED</bcp14>", "<bcp14>SHALL</bcp14>", "<bcp14>SHALL NOT</bcp14>
"MAY", and "OPTIONAL" in this document are to be interpreted as ",
described in BCP 14 <xref target="RFC2119"/> <xref target="RFC8174"/> "<bcp14>SHOULD</bcp14>", "<bcp14>SHOULD NOT</bcp14>",
when, and only when, they appear in all capitals, as shown here. "<bcp14>RECOMMENDED</bcp14>", "<bcp14>NOT RECOMMENDED</bcp14>",
</t> "<bcp14>MAY</bcp14>", and "<bcp14>OPTIONAL</bcp14>" in this document are to
be
interpreted as described in BCP&nbsp;14 <xref target="RFC2119"/> <xref
target="RFC8174"/> when, and only when, they appear in all capitals, as
shown here.
</t>
<t>The requirements language is used in <xref target="req-list"/> and applie s to implementations <t>The requirements language is used in <xref target="req-list"/> and applie s to implementations
of BIER OAM conformant to the listed requirements.</t> of BIER OAM conformant to the listed requirements.</t>
</section> </section>
<section title="Acronyms"> <section>
<t>BFD: Bidirectional Forwarding Detection <xref target="RFC85 <name>Acronyms</name>
62"/></t> <dl spacing="normal" newline="false">
<t>BFR: Bit-Forwarding Router <xref target="RFC8279"/></t> <dt>BFD:</dt><dd>Bidirectional Forwarding Detection <xref target="R
<t>BFER: Bit-Forwarding Egress Router <xref target="RFC8279"/></t FC8562"/></dd>
> <dt>BFR:</dt><dd>Bit-Forwarding Router <xref target="RFC8279"/></dd
<t>BIER: Bit Index Explicit Replication <xref target="RFC8279"/> >
</t> <dt>BFER:</dt><dd>Bit-Forwarding Egress Router <xref target="RFC827
<t>OAM: Operations, Administration, and Maintenance <xref targe 9"/></dd>
t="RFC6291"/></t> <dt>BIER:</dt><dd>Bit Index Explicit Replication <xref target="RFC8
<t>PMTUD: Path Maximum Transmission Unit Discovery <xref target="RF 279"/></dd>
C1191"/></t> <dt>OAM:</dt><dd>Operations, Administration, and Maintenance <xref
<t>p2mp: Point-to-Multipoint <xref target="RFC8562"/></t> target="RFC6291"/></dd>
<t>RDI: Remote Defect Indication <xref target="RFC6428"/></t> <dt>PMTUD:</dt><dd>Path Maximum Transmission Unit Discovery <xref t
<t>STAMP: Simple Two-way Active Measurement Protocol <xref target= arget="RFC1191"/></dd>
"RFC8762"/></t> <dt>P2MP:</dt><dd>Point-to-Multipoint <xref target="RFC8562"/></dd>
<dt>RDI:</dt><dd>Remote Defect Indication <xref target="RFC6428"/><
/dd>
<dt>STAMP:</dt><dd>Simple Two-way Active Measurement Protocol <xref
target="RFC8762"/></dd>
</dl>
</section> </section>
</section> </section>
</section> </section>
<section anchor="req-list" title="Requirements"> <section anchor="req-list">
<name>Requirements</name>
<t> <t>
This section lists the requirements for OAM of the BIER layer: This section lists the requirements for OAM of the BIER layer:
</t> </t>
<ol type="1"> <ol type="1">
<li> <li>The listed requirements <bcp14>MUST</bcp14> be supported with any
The listed requirements MUST be supported with any routing underlay <xref targ routing underlay <xref target="RFC8279"/> over which the BIER layer can be
et="RFC8279"/> over which the BIER layer can be realized. realized.</li>
</li> <li>It <bcp14>MUST</bcp14> be possible to initialize a BIER OAM session
<li> from any BFR of the given BIER domain.</li>
It MUST be possible to initialize a BIER OAM session from any BFR of the given <li>It <bcp14>MUST</bcp14> be possible to initialize a BIER OAM session from
BIER domain. a controller.</li>
</li> <li>BIER OAM <bcp14>MUST</bcp14> support proactive OAM monitoring and measur
<li> ement methods.</li>
It MUST be possible to initialize a BIER OAM session from a controller. <li>BIER OAM <bcp14>MUST</bcp14> support on-demand OAM monitoring and measur
</li> ement methods.</li>
<li> <li>BIER OAM <bcp14>MUST</bcp14> support active performance measurement meth
BIER OAM MUST support proactive OAM monitoring and measurement methods. ods <xref target="RFC7799"/>.</li>
</li> <li>BIER OAM <bcp14>MUST</bcp14> support passive performance measurement met
hods <xref target="RFC7799"/>.</li>
<li> <li>
BIER OAM MUST support on-demand OAM monitoring and measurement methods. <t>BIER OAM <bcp14>MUST</bcp14> support the ability of any BFR in the
</li> given BIER domain to proactively monitor Bit-Forwarding Egress Router (BFE
<li> R)
BIER OAM MUST support active performance measurement methods <xref target="RFC availability.</t>
7799"/>.
</li> <t>This requirement provides helpful clarification to the combination of
<li> Requirements 2 and 4. The Point-to-Multipoint (P2MP) BFD with active tail
BIER OAM MUST support passive performance measurement methods <xref target="RF support <xref
C7799"/>. target="RFC9780"/> is an example of a protocol that provides
</li> notifications about the loss of connectivity in a multicast distribution
<li> tree.</t>
BIER OAM MUST support the ability of any BFR in the given BIER </li>
domain to monitor Bit-Forwarding Egress Router (BFER) availability proactively.
</li>
</ol>
<t>
This requirement provides helpful clarification to the combination of Requiremen
ts 2 and 4. The p2mp BFD with active tail support <xref target="RFC9780"/>
is an example of a protocol that provides notifications about the loss of connec
tivity in a multicast distribution tree.
</t>
<ol start="9" type="1">
<li>
BIER OAM MUST support downstream path continuity check.
</li>
</ol>
<t>
Bidirectional Forwarding Detection (BFD) <xref target="RFC8562"/> is an exampl
e
of a protocol that monitors the continuity of a multicast distribution tree.
</t>
<ol type="1" start="10">
<li> <li>
BIER OAM MUST support downstream performance measurement. <t>BIER OAM <bcp14>MUST</bcp14> support downstream path continuity checkin
</li> g.</t>
</ol> <t>Bidirectional Forwarding Detection (BFD) <xref target="RFC8562"/> is
<t> an example of a protocol that monitors the continuity of a multicast
Simple Two-way Active Measurement Protocol (STAMP) <xref target="RFC8762"/> distribution tree.</t>
is an example
of a protocol that supports measurement of performance metrics, e.g., packet l
oss ratio, delay, and delay variation.
</t>
<ol start="11" type="1">
<li>
In the downstream direction, a BIER OAM solution MUST support
transmission of OAM packets to traverse the same set of nodes and links and
receive
the same forwarding treatment (including QoS) as the monitored BIER flow.
</li> </li>
</ol>
<t>
In some cases, e.g., when monitoring a composite data flow that includes several
sub-flows
characterized by different CoS marking, an operator may choose to monitor the co
ntinuity
of the path at the highest CoS, not at every CoS value in the data flow. In that
case, BIER OAM packets traverse
the same set of nodes and links as the composite data flow while receiving the s
ame forwarding treatment
as the highest CoS sub-flow. In this scenario, the state of path continuity for
lower CoS sub-flows can be derived from the state of the highest CoS,
as determined by the BIER OAM protocol performing continuity verification (e.g.,
BFD).
</t>
<ol start="12" type="1">
<li> <li>
BIER OAM MUST support bidirectional OAM methods. In the downstream direction, th <t>BIER OAM <bcp14>MUST</bcp14> support downstream performance measurement
ese methods .</t>
of monitoring or measurement MUST conform to Requirement 11. <t>Simple Two-way Active Measurement Protocol (STAMP) <xref
In the reverse direction (i.e., from the egress toward the ingress target="RFC8762"/> is an example of a protocol that supports measurement
endpoint of the BIER OAM test session), BIER OAM packets MAY deviate from tr of performance metrics, e.g., packet loss ratio, delay, and delay
aversing the same set of nodes and links, or variation.</t>
receive a different forwarding treatment (including QoS) as the monitored BI </li>
ER flow. <li>
</li> <t>In the downstream direction, a BIER OAM solution <bcp14>MUST</bcp14>
</ol> support transmission of OAM packets to traverse the same set of nodes
<t>Point-to-Multipoint (p2mp) BFD with active tail <xref target="RFC9780"/>) i and links and receive the same forwarding treatment (including QoS) as
s an example of the bidirectional mechanism of continuity checking. the monitored BIER flow.</t>
</t>
<ol start="13" type="1"> <t>In some cases, e.g., when monitoring a composite data flow that
<li> includes several sub-flows characterized by different Class-of-Service (Co
BIER OAM MUST support Path Maximum Transmission Unit discovery (PMTUD). S) marking, an
</li> operator may choose to monitor the continuity of the path at the highest
</ol> CoS, not at every CoS value in the data flow. In that case, BIER OAM
<t> packets traverse the same set of nodes and links as the composite data
The PMTUD using ICMP <xref target="RFC1191"/> is an example of the mechanism. flow while receiving the same forwarding treatment as the highest CoS
</t> sub-flow. In this scenario, the state of path continuity for lower CoS
<ol start="14" type="1"> sub-flows can be derived from the state of the highest CoS, as
<li> determined by the BIER OAM protocol performing continuity verification
BIER OAM MUST support an RDI mechanism to notify the BFR, the source of the cont (e.g., BFD).</t>
inuity checking by BFERs. </li>
</li> <li>
</ol> <t>BIER OAM <bcp14>MUST</bcp14> support bidirectional OAM methods. In
<t> the downstream direction, these methods of monitoring or measurement
The Diagnostic field in p2mp BFD with active tail support, as described in Secti <bcp14>MUST</bcp14> conform to Requirement 11. In the reverse direction
on 5 (i.e., from the egress toward the ingress endpoint of the BIER OAM test
of <xref target="RFC9780"/>, is an example of the RDI mechanism. session), BIER OAM packets <bcp14>MAY</bcp14> deviate from traversing
</t> the same set of nodes and links, or receive a different forwarding
<ol start="15" type="1"> treatment (including QoS) as the monitored BIER flow.</t>
<li> <t>The P2MP BFD with active tail <xref
BIER OAM MUST support downstream performance measurement method(s) that (togethe target="RFC9780"/> is an example of the bidirectional mechanism of
r) calculate performance metrics, e.g., throughput, loss, delay, continuity checking.</t>
and delay variation metrics <xref target="RFC6374"/>. </li>
</li> <li>
</ol> <t>BIER OAM <bcp14>MUST</bcp14> support Path Maximum Transmission Unit
<t> Discovery (PMTUD).</t>
STAMP (<xref target="RFC8762"/> and <xref target="RFC8972"/>) <t>The PMTUD using ICMP <xref target="RFC1191"/> is an example of the
is an example of an active performance mechanism.</t>
measurement method of performance metrics that may be applied in a BIER domain. </li>
The Alternate Marking Method, <li>
described in <xref target="RFC9341"/> and <xref target="RFC9342"/>, <t>BIER OAM <bcp14>MUST</bcp14> support an RDI mechanism to notify the
is an example of a hybrid measurement method (<xref target="RFC7799"/>) that may BFR, the source of the continuity checking by BFERs.</t>
be applied in a BIER domain. <t>The Diagnostic field in P2MP BFD with active tail support, as
</t> described in <xref section="5" target="RFC9780"/>, is an example of the
<ol start="16" type="1"> RDI mechanism.</t>
<li> </li>
BIER OAM MUST support defect notification mechanism(s). <li>
</li> <t>BIER OAM <bcp14>MUST</bcp14> support downstream performance
</ol> measurement method(s) that (together) calculate performance metrics,
<t>Alarm Indication Signal <xref target="RFC6427"/> is an example of the defect e.g., throughput, loss, delay, and delay variation metrics <xref
notification mechanism.</t> target="RFC6374"/>.</t>
<ol start="17" type="1">
<li> <t>STAMP (<xref target="RFC8762"/> and <xref target="RFC8972"/>) is an
BIER OAM MUST support a way for any BFR in the given BIER domain example of an active performance measurement method of performance
to originate a fault management message addressed to any subset of BFRs within t metrics that may be applied in a BIER domain. The Alternate-Marking
he domain. Method, described in <xref target="RFC9341"/> and <xref
</li> target="RFC9342"/>, is an example of a hybrid measurement method <xref
</ol> target="RFC7799"/> that may be applied in a BIER domain.</t>
<t><xref target="RFC6427"/> provides an example of a Fault Management messaging </li>
mechanism.</t> <li>
<ol start="18" type="1"> <t>BIER OAM <bcp14>MUST</bcp14> support defect notification
<li> mechanism(s).</t>
BIER OAM MUST support methods to enable the survivability of a BIER layer. <t>Alarm Indication Signal <xref target="RFC6427"/> is an example of the
</li> defect notification mechanism.</t>
</li>
<li>
<t>BIER OAM <bcp14>MUST</bcp14> support a way for any BFR in the given
BIER domain to originate a fault management message addressed to any
subset of BFRs within the domain.</t>
<t><xref target="RFC6427"/> provides an example of a Fault Management
messaging mechanism.</t>
</li>
<li>
<t>BIER OAM <bcp14>MUST</bcp14> support methods to enable the
survivability of a BIER layer.</t>
<t>Protection switching and restoration are examples of survivability
methods.</t>
</li>
</ol> </ol>
<t>Protection switching and restoration are examples of survivability methods. </t>
</section> </section>
<section anchor="iana-considerations" title="IANA Considerations"> <section anchor="iana-considerations">
<name>IANA Considerations</name>
<t> <t>
This document does not propose any IANA consideration. This section may be rem oved. This document has no IANA actions.
</t> </t>
</section> </section>
<section anchor="security-considerations" title="Security Considerations"> <section anchor="security-considerations">
<name>Security Considerations</name>
<t> <t>
This document lists the OAM requirements for a BIER-enabled domain and This document lists the OAM requirements for a BIER-enabled domain and
thus inherits the security considerations discussed in <xref target="RFC8279"/ it thus inherits the security considerations discussed in <xref target="RFC827
> and <xref target="RFC8296"/>. 9"/> and <xref target="RFC8296"/>.
Another general security aspect results from using active OAM protocols (<xref Another general security aspect results from using active OAM protocols <xref
target="RFC7799"/>) in a multicast network. target="RFC7799"/> in a multicast network.
</t> </t>
<t> <t>
Active OAM protocols inject specially constructed test packets. Active OAM protocols inject specially constructed test packets.
Some active OAM protocols are based on the echo request/reply principle of usi Some
ng those test packets. active OAM protocols exchange echo requests/replies
using test packets, e.g., ICMPv6 <xref target="RFC4443"/> and LSP Ping <xref
target="RFC8029"/>.
In the multicast network, test packets are replicated as data packets, In the multicast network, test packets are replicated as data packets,
thus creating a possible amplification effect of multiple echo replies being thus creating a possible amplification effect of multiple echo replies being
transmitted to the sender of the echo request. Thus, following security-related requirements for BIER OAM: transmitted to the sender of the echo request. Therefore, the following security -related requirements are defined for BIER OAM:
</t> </t>
<ul spacing="normal"> <ul spacing="normal">
<li>A BIER OAM solution MUST protect the control plane by controlling the rate o <li>A BIER OAM solution <bcp14>MUST</bcp14> protect the control plane by control
f echo request transmission.</li> ling the rate of echo request transmission.</li>
<li>A BIER OAM solution MUST provide control of the number of BIER OAM messages <li>A BIER OAM solution <bcp14>MUST</bcp14> provide control of the number of BIE
sent to the control plane.</li> R OAM messages sent to the control plane.</li>
</ul> </ul>
</section> </section>
<section anchor="Acknowledgements" numbered="true" toc="default">
<name>Acknowledgements</name>
<t>The authors would like to thank the comments and suggestions
from Gunter van de Velde that helped improve this document.</t>
</section>
</middle> </middle>
<back> <back>
<references title="Normative References">
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.R
FC.2119.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.R
FC.8174.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.R
FC.7799.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.R
FC.6374.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.R
FC.8279.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.R
FC.8296.xml"/>
<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.7799
.xml"/>
<xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.6374
.xml"/>
<xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8279
.xml"/>
<xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8296
.xml"/>
</references> </references>
<references title="Informative References"> <references>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.R <name>Informative References</name>
FC.8762.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.876
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.R 2.xml"/>
FC.8972.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.897
2.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.R <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.934
FC.9341.xml"/> 1.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RF <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.934
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<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RF <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.629
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<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RF <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.727
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<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RF <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.856
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<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RF <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.978
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<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RF <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.119
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<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RF <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.642
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<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RF <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.586
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<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RF <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.637
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<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RF <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.642
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<xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.444
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<xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.802
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</references> </references>
<section anchor="contr-sec" numbered="false" toc="default"> <section anchor="Acknowledgements" numbered="false" toc="default">
<name>Contributors' Addresses</name> <name>Acknowledgements</name>
<author initials="E." surname="Nordmark" fullname="Erik Nordmark" <t>The authors would like to thank <contact fullname="Gunter van de Velde"
> /> for the comments and suggestions that helped improve this
<organization/> document.</t>
<address> </section>
<email>nordmark@acm.org</email>
</address> <section anchor="contr-sec" numbered="false" toc="default">
<name>Contributors</name>
<author initials="E." surname="Nordmark" fullname="Erik Nordmark">
<organization/>
<address>
<email>nordmark@acm.org</email>
</address>
</author> </author>
<author initials="S." surname="Aldrin" fullname="Sam Aldrin"> <author initials="S." surname="Aldrin" fullname="Sam Aldrin">
<organization>Google</organization> <organization>Google</organization>
<address> <address>
<email>aldrin.ietf@gmail.com</email> <email>aldrin.ietf@gmail.com</email>
</address> </address>
</author> </author>
<author initials="L." surname="Zheng" fullname="Lianshu Zheng"> <author initials="L." surname="Zheng" fullname="Lianshu Zheng">
<organization/> <organization/>
<address> <address>
<email>veronique_cheng@hotmail.com</email> <email>veronique_cheng@hotmail.com</email>
</address> </address>
</author> </author>
<author initials="N." surname="Akiya" fullname="Nobo Akiya"> <author initials="N." surname="Akiya" fullname="Nobo Akiya">
<organization/> <organization/>
<address> <address>
<email>nobo.akiya.dev@gmail.com</email> <email>nobo.akiya.dev@gmail.com</email>
</address> </address>
</author> </author>
</section> </section>
</back> </back>
</rfc> </rfc>
 End of changes. 46 change blocks. 
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