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<!DOCTYPE html>
<html lang="en" class="RFC">
<head>
<meta charset="utf-8">
<meta content="Common,Latin" name="scripts">
<meta content="initial-scale=1.0" name="viewport">
<title>RFC 8745: Path Computation Element Communication Protocol (PCEP) Extensions for Associating Working and Protection Label Switched Paths (LSPs) with Stateful PCE</title>
<meta content="Hariharan Ananthakrishnan" name="author">
<meta content="Siva Sivabalan" name="author">
<meta content="Colby Barth" name="author">
<meta content="Ina Minei" name="author">
<meta content="Mahendra Singh Negi" name="author">
<meta content="
        An active stateful Path Computation Element (PCE) is capable of computing as well as controlling via 
Path Computation Element Communication Protocol (PCEP) Multiprotocol Label Switching Traffic Engineering (MPLS-TE) Label Switched Paths (LSPs).  
Furthermore, it is also possible for an active stateful PCE to create, maintain, and delete LSPs. This document defines the PCEP extension to associate two or more LSPs to provide end-to-end path protection. 
    " name="description">
<meta content="xml2rfc 2.41.0" name="generator">
<meta content="PCEP" name="keyword">
<meta content="8745" name="rfc.number">
<link href="rfc8745.xml" rel="alternate" type="application/rfc+xml">
<link href="#copyright" rel="license">
<style type="text/css">/*

  NOTE: Changes at the bottom of this file overrides some earlier settings.

  Once the style has stabilized and has been adopted as an official RFC style,
  this can be consolidated so that style settings occur only in one place, but
  for now the contents of this file consists first of the initial CSS work as
  provided to the RFC Formatter (xml2rfc) work, followed by itemized and
  commented changes found necssary during the development of the v3
  formatters.

*/

/* fonts */
@import url('https://fonts.googleapis.com/css?family=Noto+Sans'); /* Sans-serif */
@import url('https://fonts.googleapis.com/css?family=Noto+Serif'); /* Serif (print) */
@import url('https://fonts.googleapis.com/css?family=Roboto+Mono'); /* Monospace */

@viewport {
  zoom: 1.0;
  width: extend-to-zoom;
}
@-ms-viewport {
  width: extend-to-zoom;
  zoom: 1.0;
}
/* general and mobile first */
html {
}
body {
  max-width: 90%;
  margin: 1.5em auto;
  color: #222;
  background-color: #fff;
  font-size: 14px;
  font-family: 'Noto Sans', Arial, Helvetica, sans-serif;
  line-height: 1.6;
  scroll-behavior: smooth;
}
.ears {
  display: none;
}

/* headings */
#title, h1, h2, h3, h4, h5, h6 {
  margin: 1em 0 0.5em;
  font-weight: bold;
  line-height: 1.3;
}
#title {
  clear: both;
  border-bottom: 1px solid #ddd;
  margin: 0 0 0.5em 0;
  padding: 1em 0 0.5em;
}
.author {
  padding-bottom: 4px;
}
h1 {
  font-size: 26px;
  margin: 1em 0;
}
h2 {
  font-size: 22px;
  margin-top: -20px;  /* provide offset for in-page anchors */
  padding-top: 33px;
}
h3 {
  font-size: 18px;
  margin-top: -36px;  /* provide offset for in-page anchors */
  padding-top: 42px;
}
h4 {
  font-size: 16px;
  margin-top: -36px;  /* provide offset for in-page anchors */
  padding-top: 42px;
}
h5, h6 {
  font-size: 14px;
}
#n-copyright-notice {
  border-bottom: 1px solid #ddd;
  padding-bottom: 1em;
  margin-bottom: 1em;
}
/* general structure */
p {
  padding: 0;
  margin: 0 0 1em 0;
  text-align: left;
}
div, span {
  position: relative;
}
div {
  margin: 0;
}
.alignRight.art-text {
  background-color: #f9f9f9;
  border: 1px solid #eee;
  border-radius: 3px;
  padding: 1em 1em 0;
  margin-bottom: 1.5em;
}
.alignRight.art-text pre {
  padding: 0;
}
.alignRight {
  margin: 1em 0;
}
.alignRight > *:first-child {
  border: none;
  margin: 0;
  float: right;
  clear: both;
}
.alignRight > *:nth-child(2) {
  clear: both;
  display: block;
  border: none;
}
svg {
  display: block;
}
.alignCenter.art-text {
  background-color: #f9f9f9;
  border: 1px solid #eee;
  border-radius: 3px;
  padding: 1em 1em 0;
  margin-bottom: 1.5em;
}
.alignCenter.art-text pre {
  padding: 0;
}
.alignCenter {
  margin: 1em 0;
}
.alignCenter > *:first-child {
  border: none;
  /* this isn't optimal, but it's an existence proof.  PrinceXML doesn't
     support flexbox yet.
  */
  display: table;
  margin: 0 auto;
}

/* lists */
ol, ul {
  padding: 0;
  margin: 0 0 1em 2em;
}
ol ol, ul ul, ol ul, ul ol {
  margin-left: 1em;
}
li {
  margin: 0 0 0.25em 0;
}
.ulCompact li {
  margin: 0;
}
ul.empty, .ulEmpty {
  list-style-type: none;
}
ul.empty li, .ulEmpty li {
  margin-top: 0.5em;
}
ul.compact, .ulCompact,
ol.compact, .olCompact {
  line-height: 100%;
  margin: 0 0 0 2em;
}

/* definition lists */
dl {
}
dl > dt {
  float: left;
  margin-right: 1em;
}
/* 
dl.nohang > dt {
  float: none;
}
*/
dl > dd {
  margin-bottom: .8em;
  min-height: 1.3em;
}
dl.compact > dd, .dlCompact > dd {
  margin-bottom: 0em;
}
dl > dd > dl {
  margin-top: 0.5em;
  margin-bottom: 0em;
}

/* links */
a {
  text-decoration: none;
}
a[href] {
  color: #22e; /* Arlen: WCAG 2019 */
}
a[href]:hover {
  background-color: #f2f2f2;
}
figcaption a[href],
a[href].selfRef {
  color: #222;
}
/* XXX probably not this:
a.selfRef:hover {
  background-color: transparent;
  cursor: default;
} */

/* Figures */
tt, code, pre, code {
  background-color: #f9f9f9;
  font-family: 'Roboto Mono', monospace;
}
pre {
  border: 1px solid #eee;
  margin: 0;
  padding: 1em;
}
img {
  max-width: 100%;
}
figure {
  margin: 0;
}
figure blockquote {
  margin: 0.8em 0.4em 0.4em;
}
figcaption {
  font-style: italic;
  margin: 0 0 1em 0;
}
@media screen {
  pre {
    overflow-x: auto;
    max-width: 100%;
    max-width: calc(100% - 22px);
  }
}

/* aside, blockquote */
aside, blockquote {
  margin-left: 0;
  padding: 1.2em 2em;
}
blockquote {
  background-color: #f9f9f9;
  color: #111; /* Arlen: WCAG 2019 */
  border: 1px solid #ddd;
  border-radius: 3px;
  margin: 1em 0;
}
cite {
  display: block;
  text-align: right;
  font-style: italic;
}

/* tables */
table {
  width: 100%;
  margin: 0 0 1em;
  border-collapse: collapse;
  border: 1px solid #eee;
}
th, td {
  text-align: left;
  vertical-align: top;
  padding: 0.5em 0.75em;
}
th {
  text-align: left;
  background-color: #e9e9e9;
}
tr:nth-child(2n+1) > td {
  background-color: #f5f5f5;
}
table caption {
  font-style: italic;
  margin: 0;
  padding: 0;
  text-align: left;
}
table p {
  /* XXX to avoid bottom margin on table row signifiers. If paragraphs should
     be allowed within tables more generally, it would be far better to select on a class. */
  margin: 0;
}

/* pilcrow */
a.pilcrow {
  color: #666; /* Arlen: AHDJ 2019 */
  text-decoration: none;
  visibility: hidden;
  user-select: none;
  -ms-user-select: none;
  -o-user-select:none;
  -moz-user-select: none;
  -khtml-user-select: none;
  -webkit-user-select: none;
  -webkit-touch-callout: none;
}
@media screen {
  aside:hover > a.pilcrow,
  p:hover > a.pilcrow,
  blockquote:hover > a.pilcrow,
  div:hover > a.pilcrow,
  li:hover > a.pilcrow,
  pre:hover > a.pilcrow {
    visibility: visible;
  }
  a.pilcrow:hover {
    background-color: transparent;
  }
}

/* misc */
hr {
  border: 0;
  border-top: 1px solid #eee;
}
.bcp14 {
  font-variant: small-caps;
}

.role {
  font-variant: all-small-caps;
}

/* info block */
#identifiers {
  margin: 0;
  font-size: 0.9em;
}
#identifiers dt {
  width: 3em;
  clear: left;
}
#identifiers dd {
  float: left;
  margin-bottom: 0;
}
#identifiers .authors .author {
  display: inline-block;
  margin-right: 1.5em;
}
#identifiers .authors .org {
  font-style: italic;
}

/* The prepared/rendered info at the very bottom of the page */
.docInfo {
  color: #666; /* Arlen: WCAG 2019 */
  font-size: 0.9em;
  font-style: italic;
  margin-top: 2em;
}
.docInfo .prepared {
  float: left;
}
.docInfo .prepared {
  float: right;
}

/* table of contents */
#toc  {
  padding: 0.75em 0 2em 0;
  margin-bottom: 1em;
}
nav.toc ul {
  margin: 0 0.5em 0 0;
  padding: 0;
  list-style: none;
}
nav.toc li {
  line-height: 1.3em;
  margin: 0.75em 0;
  padding-left: 1.2em;
  text-indent: -1.2em;
}
/* references */
.references dt {
  text-align: right;
  font-weight: bold;
  min-width: 7em;
}
.references dd {
  margin-left: 8em;
  overflow: auto;
}

.refInstance {
  margin-bottom: 1.25em;
}

.references .ascii {
  margin-bottom: 0.25em;
}

/* index */
.index ul {
  margin: 0 0 0 1em;
  padding: 0;
  list-style: none;
}
.index ul ul {
  margin: 0;
}
.index li {
  margin: 0;
  text-indent: -2em;
  padding-left: 2em;
  padding-bottom: 5px;
}
.indexIndex {
  margin: 0.5em 0 1em;
}
.index a {
  font-weight: 700;
}
/* make the index two-column on all but the smallest screens */
@media (min-width: 600px) {
  .index ul {
    -moz-column-count: 2;
    -moz-column-gap: 20px;
  }
  .index ul ul {
    -moz-column-count: 1;
    -moz-column-gap: 0;
  }
}

/* authors */
address.vcard {
  font-style: normal;
  margin: 1em 0;
}

address.vcard .nameRole {
  font-weight: 700;
  margin-left: 0;
}
address.vcard .label {
  font-family: "Noto Sans",Arial,Helvetica,sans-serif;
  margin: 0.5em 0;
}
address.vcard .type {
  display: none;
}
.alternative-contact {
  margin: 1.5em 0 1em;
}
hr.addr {
  border-top: 1px dashed;
  margin: 0;
  color: #ddd;
  max-width: calc(100% - 16px);
}

/* temporary notes */
.rfcEditorRemove::before {
  position: absolute;
  top: 0.2em;
  right: 0.2em;
  padding: 0.2em;
  content: "The RFC Editor will remove this note";
  color: #9e2a00; /* Arlen: WCAG 2019 */
  background-color: #ffd; /* Arlen: WCAG 2019 */
}
.rfcEditorRemove {
  position: relative;
  padding-top: 1.8em;
  background-color: #ffd; /* Arlen: WCAG 2019 */
  border-radius: 3px;
}
.cref {
  background-color: #ffd; /* Arlen: WCAG 2019 */
  padding: 2px 4px;
}
.crefSource {
  font-style: italic;
}
/* alternative layout for smaller screens */
@media screen and (max-width: 1023px) {
  body {
    padding-top: 2em;
  }
  #title {
    padding: 1em 0;
  }
  h1 {
    font-size: 24px;
  }
  h2 {
    font-size: 20px;
    margin-top: -18px;  /* provide offset for in-page anchors */
    padding-top: 38px;
  }
  #identifiers dd {
    max-width: 60%;
  }
  #toc {
    position: fixed;
    z-index: 2;
    top: 0;
    right: 0;
    padding: 0;
    margin: 0;
    background-color: inherit;
    border-bottom: 1px solid #ccc;
  }
  #toc h2 {
    margin: -1px 0 0 0;
    padding: 4px 0 4px 6px;
    padding-right: 1em;
    min-width: 190px;
    font-size: 1.1em;
    text-align: right;
    background-color: #444;
    color: white;
    cursor: pointer;
  }
  #toc h2::before { /* css hamburger */
    float: right;
    position: relative;
    width: 1em;
    height: 1px;
    left: -164px;
    margin: 6px 0 0 0;
    background: white none repeat scroll 0 0;
    box-shadow: 0 4px 0 0 white, 0 8px 0 0 white;
    content: "";
  }
  #toc nav {
    display: none;
    padding: 0.5em 1em 1em;
    overflow: auto;
    height: calc(100vh - 48px);
    border-left: 1px solid #ddd;
  }
}

/* alternative layout for wide screens */
@media screen and (min-width: 1024px) {
  body {
    max-width: 724px;
    margin: 42px auto;
    padding-left: 1.5em;
    padding-right: 29em;
  }
  #toc {
    position: fixed;
    top: 42px;
    right: 42px;
    width: 25%;
    margin: 0;
    padding: 0 1em;
    z-index: 1;
  }
  #toc h2 {
    border-top: none;
    border-bottom: 1px solid #ddd;
    font-size: 1em;
    font-weight: normal;
    margin: 0;
    padding: 0.25em 1em 1em 0;
  }
  #toc nav {
    display: block;
    height: calc(90vh - 84px);
    bottom: 0;
    padding: 0.5em 0 0;
    overflow: auto;
  }
  img { /* future proofing */
    max-width: 100%;
    height: auto;
  }
}

/* pagination */
@media print {
  body {

    width: 100%;
  }
  p {
    orphans: 3;
    widows: 3;
  }
  #n-copyright-notice {
    border-bottom: none;
  }
  #toc, #n-introduction {
    page-break-before: always;
  }
  #toc {
    border-top: none;
    padding-top: 0;
  }
  figure, pre {
    page-break-inside: avoid;
  }
  figure {
    overflow: scroll;
  }
  h1, h2, h3, h4, h5, h6 {
    page-break-after: avoid;
  }
  h2+*, h3+*, h4+*, h5+*, h6+* {
    page-break-before: avoid;
  }
  pre {
    white-space: pre-wrap;
    word-wrap: break-word;
    font-size: 10pt;
  }
  table {
    border: 1px solid #ddd;
  }
  td {
    border-top: 1px solid #ddd;
  }
}

/* This is commented out here, as the string-set: doesn't
   pass W3C validation currently */
/*
.ears thead .left {
  string-set: ears-top-left content();
}

.ears thead .center {
  string-set: ears-top-center content();
}

.ears thead .right {
  string-set: ears-top-right content();
}

.ears tfoot .left {
  string-set: ears-bottom-left content();
}

.ears tfoot .center {
  string-set: ears-bottom-center content();
}

.ears tfoot .right {
  string-set: ears-bottom-right content();
}
*/

@page :first {
  padding-top: 0;
  @top-left {
    content: normal;
    border: none;
  }
  @top-center {
    content: normal;
    border: none;
  }
  @top-right {
    content: normal;
    border: none;
  }
}

@page {
  size: A4;
  margin-bottom: 45mm;
  padding-top: 20px;
  /* The follwing is commented out here, but set appropriately by in code, as
     the content depends on the document */
  /*
  @top-left {
    content: 'Internet-Draft';
    vertical-align: bottom;
    border-bottom: solid 1px #ccc;
  }
  @top-left {
    content: string(ears-top-left);
    vertical-align: bottom;
    border-bottom: solid 1px #ccc;
  }
  @top-center {
    content: string(ears-top-center);
    vertical-align: bottom;
    border-bottom: solid 1px #ccc;
  }
  @top-right {
    content: string(ears-top-right);
    vertical-align: bottom;
    border-bottom: solid 1px #ccc;
  }
  @bottom-left {
    content: string(ears-bottom-left);
    vertical-align: top;
    border-top: solid 1px #ccc;
  }
  @bottom-center {
    content: string(ears-bottom-center);
    vertical-align: top;
    border-top: solid 1px #ccc;
  }
  @bottom-right {
      content: '[Page ' counter(page) ']';
      vertical-align: top;
      border-top: solid 1px #ccc;
  }
  */

}

/* Changes introduced to fix issues found during implementation */
/* Make sure links are clickable even if overlapped by following H* */
a {
  z-index: 2;
}
/* Separate body from document info even without intervening H1 */
section {
  clear: both;
}


/* Top align author divs, to avoid names without organization dropping level with org names */
.author {
  vertical-align: top;
}

/* Leave room in document info to show Internet-Draft on one line */
#identifiers dt {
  width: 8em;
}

/* Don't waste quite as much whitespace between label and value in doc info */
#identifiers dd {
  margin-left: 1em;
}

/* Give floating toc a background color (needed when it's a div inside section */
#toc {
  background-color: white;
}

/* Make the collapsed ToC header render white on gray also when it's a link */
@media screen and (max-width: 1023px) {
  #toc h2 a,
  #toc h2 a:link,
  #toc h2 a:focus,
  #toc h2 a:hover,
  #toc a.toplink,
  #toc a.toplink:hover {
    color: white;
    background-color: #444;
    text-decoration: none;
  }
}

/* Give the bottom of the ToC some whitespace */
@media screen and (min-width: 1024px) {
  #toc {
    padding: 0 0 1em 1em;
  }
}

/* Style section numbers with more space between number and title */
.section-number {
  padding-right: 0.5em;
}

/* prevent monospace from becoming overly large */
tt, code, pre, code {
  font-size: 95%;
}

/* Fix the height/width aspect for ascii art*/
pre.sourcecode,
.art-text pre {
  line-height: 1.12;
}


/* Add styling for a link in the ToC that points to the top of the document */
a.toplink {
  float: right;
  margin-right: 0.5em;
}

/* Fix the dl styling to match the RFC 7992 attributes */
dl > dt,
dl.dlParallel > dt {
  float: left;
  margin-right: 1em;
}
dl.dlNewline > dt {
  float: none;
}

/* Provide styling for table cell text alignment */
table td.text-left,
table th.text-left {
  text-align: left;
}
table td.text-center,
table th.text-center {
  text-align: center;
}
table td.text-right,
table th.text-right {
  text-align: right;
}

/* Make the alternative author contact informatio look less like just another
   author, and group it closer with the primary author contact information */
.alternative-contact {
  margin: 0.5em 0 0.25em 0;
}
address .non-ascii {
  margin: 0 0 0 2em;
}

/* With it being possible to set tables with alignment
  left, center, and right, { width: 100%; } does not make sense */
table {
  width: auto;
}

/* Avoid reference text that sits in a block with very wide left margin,
   because of a long floating dt label.*/
.references dd {
  overflow: visible;
}

/* Control caption placement */
caption {
  caption-side: bottom;
}

/* Limit the width of the author address vcard, so names in right-to-left
   script don't end up on the other side of the page. */

address.vcard {
  max-width: 30em;
  margin-right: auto;
}

/* For address alignment dependent on LTR or RTL scripts */
address div.left {
  text-align: left;
}
address div.right {
  text-align: right;
}

/* Provide table alignment support.  We can't use the alignX classes above
   since they do unwanted things with caption and other styling. */
table.right {
 margin-left: auto;
 margin-right: 0;
}
table.center {
 margin-left: auto;
 margin-right: auto;
}
table.left {
 margin-left: 0;
 margin-right: auto;
}

/* Give the table caption label the same styling as the figcaption */
caption a[href] {
  color: #222;
}

@media print {
  .toplink {
    display: none;
  }

  /* avoid overwriting the top border line with the ToC header */
  #toc {
    padding-top: 1px;
  }

  /* Avoid page breaks inside dl and author address entries */
  .vcard {
    page-break-inside: avoid;
  }

}
/* Avoid wrapping of URLs in references */
@media screen {
  .references a {
    white-space: nowrap;
  }
}
/* Tweak the bcp14 keyword presentation */
.bcp14 {
  font-variant: small-caps;
  font-weight: bold;
  font-size: 0.9em;
}
/* Tweak the invisible space above H* in order not to overlay links in text above */
 h2 {
  margin-top: -18px;  /* provide offset for in-page anchors */
  padding-top: 31px;
 }
 h3 {
  margin-top: -18px;  /* provide offset for in-page anchors */
  padding-top: 24px;
 }
 h4 {
  margin-top: -18px;  /* provide offset for in-page anchors */
  padding-top: 24px;
 }
/* Float artwork pilcrow to the right */
@media screen {
  .artwork a.pilcrow {
    display: block;
    line-height: 0.7;
    margin-top: 0.15em;
  }
}
/* Make pilcrows on dd visible */
@media screen {
  dd:hover > a.pilcrow {
    visibility: visible;
  }
}
/* Make the placement of figcaption match that of a table's caption
   by removing the figure's added bottom margin */
.alignLeft.art-text,
.alignCenter.art-text,
.alignRight.art-text {
   margin-bottom: 0;
}
.alignLeft,
.alignCenter,
.alignRight {
  margin: 1em 0 0 0;
}
/* In print, the pilcrow won't show on hover, so prevent it from taking up space,
   possibly even requiring a new line */
@media print {
  a.pilcrow {
    display: none;
  }
}
/* Styling for the external metadata */
div#external-metadata {
  background-color: #eee;
  padding: 0.5em;
  margin-bottom: 0.5em;
  display: none;
}
div#internal-metadata {
  padding: 0.5em;                       /* to match the external-metadata padding */
}
/* Styling for title RFC Number */
h1#rfcnum {
  clear: both;
  margin: 0 0 -1em;
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<link href="https://dx.doi.org/10.17487/rfc8745" rel="alternate">
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<table class="ears">
<thead><tr>
<td class="left">RFC 8745</td>
<td class="center">Stateful PCE LSP Path Protection</td>
<td class="right">March 2020</td>
</tr></thead>
<tfoot><tr>
<td class="left">Ananthakrishnan, et al.</td>
<td class="center">Standards Track</td>
<td class="right">[Page]</td>
</tr></tfoot>
</table>
<div id="external-metadata" class="document-information"></div>
<div id="internal-metadata" class="document-information">
<dl id="identifiers">
<dt class="label-stream">Stream:</dt>
<dd class="stream">Internet Engineering Task Force (IETF)</dd>
<dt class="label-rfc">RFC:</dt>
<dd class="rfc"><a href="https://www.rfc-editor.org/rfc/rfc8745" class="eref">8745</a></dd>
<dt class="label-category">Category:</dt>
<dd class="category">Standards Track</dd>
<dt class="label-published">Published:</dt>
<dd class="published">
<time datetime="2020-03" class="published">March 2020</time>
    </dd>
<dt class="label-issn">ISSN:</dt>
<dd class="issn">2070-1721</dd>
<dt class="label-authors">Authors:</dt>
<dd class="authors">
<div class="author">
      <div class="author-name">H. Ananthakrishnan</div>
<div class="org">Netflix</div>
</div>
<div class="author">
      <div class="author-name">S. Sivabalan</div>
<div class="org">Cisco</div>
</div>
<div class="author">
      <div class="author-name">C. Barth</div>
<div class="org">Juniper Networks</div>
</div>
<div class="author">
      <div class="author-name">I. Minei</div>
<div class="org">Google, Inc</div>
</div>
<div class="author">
      <div class="author-name">M. Negi</div>
<div class="org">Huawei Technologies</div>
</div>
</dd>
</dl>
</div>
<h1 id="rfcnum">RFC 8745</h1>
<h1 id="title">Path Computation Element Communication Protocol (PCEP) Extensions for Associating Working and Protection Label Switched Paths (LSPs) with Stateful PCE</h1>
<section id="section-abstract">
      <h2 id="abstract"><a href="#abstract" class="selfRef">Abstract</a></h2>
<p id="section-abstract-1"> An active stateful Path Computation Element (PCE) is capable of computing as well as controlling via 
Path Computation Element Communication Protocol (PCEP) Multiprotocol Label Switching Traffic Engineering (MPLS-TE) Label Switched Paths (LSPs).  
Furthermore, it is also possible for an active stateful PCE to create, maintain, and delete LSPs. This document defines the PCEP extension to associate two or more LSPs to provide end-to-end path protection.<a href="#section-abstract-1" class="pilcrow">¶</a></p>
</section>
<div id="status-of-memo">
<section id="section-boilerplate.1">
        <h2 id="name-status-of-this-memo">
<a href="#name-status-of-this-memo" class="section-name selfRef">Status of This Memo</a>
        </h2>
<p id="section-boilerplate.1-1">
            This is an Internet Standards Track document.<a href="#section-boilerplate.1-1" class="pilcrow">¶</a></p>
<p id="section-boilerplate.1-2">
            This document is a product of the Internet Engineering Task Force
            (IETF).  It represents the consensus of the IETF community.  It has
            received public review and has been approved for publication by
            the Internet Engineering Steering Group (IESG).  Further
            information on Internet Standards is available in Section 2 of 
            RFC 7841.<a href="#section-boilerplate.1-2" class="pilcrow">¶</a></p>
<p id="section-boilerplate.1-3">
            Information about the current status of this document, any
            errata, and how to provide feedback on it may be obtained at
            <span><a href="https://www.rfc-editor.org/info/rfc8745">https://www.rfc-editor.org/info/rfc8745</a></span>.<a href="#section-boilerplate.1-3" class="pilcrow">¶</a></p>
</section>
</div>
<div id="copyright">
<section id="section-boilerplate.2">
        <h2 id="name-copyright-notice">
<a href="#name-copyright-notice" class="section-name selfRef">Copyright Notice</a>
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            Copyright (c) 2020 IETF Trust and the persons identified as the
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            This document is subject to BCP 78 and the IETF Trust's Legal
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            publication of this document. Please review these documents
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            document must include Simplified BSD License text as described in
            Section 4.e of the Trust Legal Provisions and are provided without
            warranty as described in the Simplified BSD License.<a href="#section-boilerplate.2-2" class="pilcrow">¶</a></p>
</section>
</div>
<div id="toc">
<section id="section-toc.1">
        <a href="#" onclick="scroll(0,0)" class="toplink">▲</a><h2 id="name-table-of-contents">
<a href="#name-table-of-contents" class="section-name selfRef">Table of Contents</a>
        </h2>
<nav class="toc"><ul class="toc ulEmpty">
<li class="toc ulEmpty" id="section-toc.1-1.1">
            <p id="section-toc.1-1.1.1"><a href="#section-1" class="xref">1</a>.  <a href="#name-introduction" class="xref">Introduction</a><a href="#section-toc.1-1.1.1" class="pilcrow">¶</a></p>
<ul class="toc ulEmpty">
<li class="toc ulEmpty" id="section-toc.1-1.1.2.1">
                <p id="section-toc.1-1.1.2.1.1"><a href="#section-1.1" class="xref">1.1</a>.  <a href="#name-requirements-language" class="xref">Requirements Language</a><a href="#section-toc.1-1.1.2.1.1" class="pilcrow">¶</a></p>
</li>
</ul>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.2">
            <p id="section-toc.1-1.2.1"><a href="#section-2" class="xref">2</a>.  <a href="#name-terminology" class="xref">Terminology</a><a href="#section-toc.1-1.2.1" class="pilcrow">¶</a></p>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.3">
            <p id="section-toc.1-1.3.1"><a href="#section-3" class="xref">3</a>.  <a href="#name-pcep-extensions" class="xref">PCEP Extensions</a><a href="#section-toc.1-1.3.1" class="pilcrow">¶</a></p>
<ul class="toc ulEmpty">
<li class="toc ulEmpty" id="section-toc.1-1.3.2.1">
                <p id="section-toc.1-1.3.2.1.1"><a href="#section-3.1" class="xref">3.1</a>.  <a href="#name-path-protection-association" class="xref">Path Protection Association Type</a><a href="#section-toc.1-1.3.2.1.1" class="pilcrow">¶</a></p>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.3.2.2">
                <p id="section-toc.1-1.3.2.2.1"><a href="#section-3.2" class="xref">3.2</a>.  <a href="#name-path-protection-association-" class="xref">Path Protection Association TLV</a><a href="#section-toc.1-1.3.2.2.1" class="pilcrow">¶</a></p>
</li>
</ul>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.4">
            <p id="section-toc.1-1.4.1"><a href="#section-4" class="xref">4</a>.  <a href="#name-operation" class="xref">Operation</a><a href="#section-toc.1-1.4.1" class="pilcrow">¶</a></p>
<ul class="toc ulEmpty">
<li class="toc ulEmpty" id="section-toc.1-1.4.2.1">
                <p id="section-toc.1-1.4.2.1.1"><a href="#section-4.1" class="xref">4.1</a>.  <a href="#name-state-synchronization" class="xref">State Synchronization</a><a href="#section-toc.1-1.4.2.1.1" class="pilcrow">¶</a></p>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.4.2.2">
                <p id="section-toc.1-1.4.2.2.1"><a href="#section-4.2" class="xref">4.2</a>.  <a href="#name-pcc-initiated-lsps" class="xref">PCC-Initiated LSPs</a><a href="#section-toc.1-1.4.2.2.1" class="pilcrow">¶</a></p>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.4.2.3">
                <p id="section-toc.1-1.4.2.3.1"><a href="#section-4.3" class="xref">4.3</a>.  <a href="#name-pce-initiated-lsps" class="xref">PCE-Initiated LSPs</a><a href="#section-toc.1-1.4.2.3.1" class="pilcrow">¶</a></p>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.4.2.4">
                <p id="section-toc.1-1.4.2.4.1"><a href="#section-4.4" class="xref">4.4</a>.  <a href="#name-session-termination" class="xref">Session Termination</a><a href="#section-toc.1-1.4.2.4.1" class="pilcrow">¶</a></p>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.4.2.5">
                <p id="section-toc.1-1.4.2.5.1"><a href="#section-4.5" class="xref">4.5</a>.  <a href="#name-error-handling" class="xref">Error Handling</a><a href="#section-toc.1-1.4.2.5.1" class="pilcrow">¶</a></p>
</li>
</ul>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.5">
            <p id="section-toc.1-1.5.1"><a href="#section-5" class="xref">5</a>.  <a href="#name-other-considerations" class="xref">Other Considerations</a><a href="#section-toc.1-1.5.1" class="pilcrow">¶</a></p>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.6">
            <p id="section-toc.1-1.6.1"><a href="#section-6" class="xref">6</a>.  <a href="#name-iana-considerations" class="xref">IANA Considerations</a><a href="#section-toc.1-1.6.1" class="pilcrow">¶</a></p>
<ul class="toc ulEmpty">
<li class="toc ulEmpty" id="section-toc.1-1.6.2.1">
                <p id="section-toc.1-1.6.2.1.1"><a href="#section-6.1" class="xref">6.1</a>.  <a href="#name-association-type" class="xref">Association Type</a><a href="#section-toc.1-1.6.2.1.1" class="pilcrow">¶</a></p>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.6.2.2">
                <p id="section-toc.1-1.6.2.2.1"><a href="#section-6.2" class="xref">6.2</a>.  <a href="#name-path-protection-association-tl" class="xref">Path Protection Association TLV</a><a href="#section-toc.1-1.6.2.2.1" class="pilcrow">¶</a></p>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.6.2.3">
                <p id="section-toc.1-1.6.2.3.1"><a href="#section-6.3" class="xref">6.3</a>.  <a href="#name-pcep-errors" class="xref">PCEP Errors</a><a href="#section-toc.1-1.6.2.3.1" class="pilcrow">¶</a></p>
</li>
</ul>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.7">
            <p id="section-toc.1-1.7.1"><a href="#section-7" class="xref">7</a>.  <a href="#name-security-considerations" class="xref">Security Considerations</a><a href="#section-toc.1-1.7.1" class="pilcrow">¶</a></p>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.8">
            <p id="section-toc.1-1.8.1"><a href="#section-8" class="xref">8</a>.  <a href="#name-manageability-consideration" class="xref">Manageability Considerations</a><a href="#section-toc.1-1.8.1" class="pilcrow">¶</a></p>
<ul class="toc ulEmpty">
<li class="toc ulEmpty" id="section-toc.1-1.8.2.1">
                <p id="section-toc.1-1.8.2.1.1"><a href="#section-8.1" class="xref">8.1</a>.  <a href="#name-control-of-function-and-pol" class="xref">Control of Function and Policy</a><a href="#section-toc.1-1.8.2.1.1" class="pilcrow">¶</a></p>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.8.2.2">
                <p id="section-toc.1-1.8.2.2.1"><a href="#section-8.2" class="xref">8.2</a>.  <a href="#name-information-and-data-models" class="xref">Information and Data Models</a><a href="#section-toc.1-1.8.2.2.1" class="pilcrow">¶</a></p>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.8.2.3">
                <p id="section-toc.1-1.8.2.3.1"><a href="#section-8.3" class="xref">8.3</a>.  <a href="#name-liveness-detection-and-moni" class="xref">Liveness Detection and Monitoring</a><a href="#section-toc.1-1.8.2.3.1" class="pilcrow">¶</a></p>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.8.2.4">
                <p id="section-toc.1-1.8.2.4.1"><a href="#section-8.4" class="xref">8.4</a>.  <a href="#name-verify-correct-operations" class="xref">Verify Correct Operations</a><a href="#section-toc.1-1.8.2.4.1" class="pilcrow">¶</a></p>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.8.2.5">
                <p id="section-toc.1-1.8.2.5.1"><a href="#section-8.5" class="xref">8.5</a>.  <a href="#name-requirements-on-other-proto" class="xref">Requirements on Other Protocols</a><a href="#section-toc.1-1.8.2.5.1" class="pilcrow">¶</a></p>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.8.2.6">
                <p id="section-toc.1-1.8.2.6.1"><a href="#section-8.6" class="xref">8.6</a>.  <a href="#name-impact-on-network-operation" class="xref">Impact on Network Operations</a><a href="#section-toc.1-1.8.2.6.1" class="pilcrow">¶</a></p>
</li>
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<li class="toc ulEmpty" id="section-toc.1-1.9">
            <p id="section-toc.1-1.9.1"><a href="#section-9" class="xref">9</a>.  <a href="#name-references" class="xref">References</a><a href="#section-toc.1-1.9.1" class="pilcrow">¶</a></p>
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<li class="toc ulEmpty" id="section-toc.1-1.9.2.1">
                <p id="section-toc.1-1.9.2.1.1"><a href="#section-9.1" class="xref">9.1</a>.  <a href="#name-normative-references" class="xref">Normative References</a><a href="#section-toc.1-1.9.2.1.1" class="pilcrow">¶</a></p>
</li>
<li class="toc ulEmpty" id="section-toc.1-1.9.2.2">
                <p id="section-toc.1-1.9.2.2.1"><a href="#section-9.2" class="xref">9.2</a>.  <a href="#name-informative-references" class="xref">Informative References</a><a href="#section-toc.1-1.9.2.2.1" class="pilcrow">¶</a></p>
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            <p id="section-toc.1-1.10.1"><a href="#section-appendix.a" class="xref"></a><a href="#name-acknowledgments" class="xref">Acknowledgments</a><a href="#section-toc.1-1.10.1" class="pilcrow">¶</a></p>
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            <p id="section-toc.1-1.11.1"><a href="#section-appendix.b" class="xref"></a><a href="#name-contributors" class="xref">Contributors</a><a href="#section-toc.1-1.11.1" class="pilcrow">¶</a></p>
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            <p id="section-toc.1-1.12.1"><a href="#section-appendix.c" class="xref"></a><a href="#name-authors-addresses" class="xref">Authors' Addresses</a><a href="#section-toc.1-1.12.1" class="pilcrow">¶</a></p>
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</div>
<section id="section-1">
      <h2 id="name-introduction">
<a href="#section-1" class="section-number selfRef">1. </a><a href="#name-introduction" class="section-name selfRef">Introduction</a>
      </h2>
<p id="section-1-1"><span>[<a href="#RFC5440" class="xref">RFC5440</a>]</span> describes Path Computation
      Element Communication Protocol (PCEP) for communication between a Path
      Computation Client (PCC) and a PCE or between a pair of PCEs as per
      <span>[<a href="#RFC4655" class="xref">RFC4655</a>]</span>.  A PCE computes paths for
      MPLS-TE Label Switched Paths (LSPs) based on various constraints and
      optimization criteria.<a href="#section-1-1" class="pilcrow">¶</a></p>
<p id="section-1-2">Stateful PCE <span>[<a href="#RFC8231" class="xref">RFC8231</a>]</span> specifies a set of extensions to PCEP to enable 
stateful control of paths such as MPLS-TE LSPs between and across PCEP sessions in compliance with <span>[<a href="#RFC4657" class="xref">RFC4657</a>]</span>. 
It includes mechanisms to affect LSP state synchronization between PCCs and PCEs,
delegation of control of LSPs to PCEs, and PCE control of timing and
sequence of path computations within and across PCEP sessions. The
focus is on a model where LSPs are configured on the PCC, and control
over them is delegated to the stateful PCE.

Furthermore, <span>[<a href="#RFC8281" class="xref">RFC8281</a>]</span> specifies a mechanism to
dynamically instantiate LSPs on a PCC based on the requests from a
stateful PCE or a controller using stateful PCE.<a href="#section-1-2" class="pilcrow">¶</a></p>
<p id="section-1-3">Path protection <span>[<a href="#RFC4427" class="xref">RFC4427</a>]</span> refers to a
      paradigm in which the working LSP is protected by one or more protection
      LSP(s).  When the working LSP fails, protection LSP(s) is/are
      activated. When the working LSPs are computed and controlled by the PCE,
      there is benefit in a mode of operation where protection LSPs are also
      computed and controlled by the same PCE. <span>[<a href="#RFC8051" class="xref">RFC8051</a>]</span> describes the applicability of path protection in PCE
      deployments.<a href="#section-1-3" class="pilcrow">¶</a></p>
<p id="section-1-4">This document specifies a stateful PCEP extension to associate two or
      more LSPs for the purpose of setting up path protection. The extension
      defined in this document covers the following scenarios:<a href="#section-1-4" class="pilcrow">¶</a></p>
<ul>
<li id="section-1-5.1">A PCC initiates a protection LSP and retains the control of the
        LSP. The PCC computes the path itself or makes a request for path
        computation to a PCE. After the path setup, it reports the information
        and state of the path to the PCE.  This includes the association group
        identifying the working and protection LSPs.  This is the passive
        stateful mode <span>[<a href="#RFC8051" class="xref">RFC8051</a>]</span>.<a href="#section-1-5.1" class="pilcrow">¶</a>
</li>
<li id="section-1-5.2">A PCC initiates a protection LSP and delegates the control of the
        LSP to a stateful PCE. During delegation, the association group
        identifying the working and protection LSPs is included. The PCE
        computes the path for the protection LSP and updates the PCC with the
        information about the path as long as it controls the LSP.  This is
        the active stateful mode <span>[<a href="#RFC8051" class="xref">RFC8051</a>]</span>.<a href="#section-1-5.2" class="pilcrow">¶</a>
</li>
<li id="section-1-5.3">A protection LSP could be initiated by a stateful PCE, which retains the control of the LSP. 
    The PCE is responsible for computing the path of the LSP and updating to the PCC with the information about the path. 
    This is the PCE-Initiated mode <span>[<a href="#RFC8281" class="xref">RFC8281</a>]</span>.<a href="#section-1-5.3" class="pilcrow">¶</a>
</li>
</ul>
<p id="section-1-6">


   Note that a protection LSP can be established (signaled) before
   the failure (in which case the LSP is said to be either in standby mode
   <span>[<a href="#RFC4427" class="xref">RFC4427</a>]</span> or a primary LSP <span>[<a href="#RFC4872" class="xref">RFC4872</a>]</span>) or after failure of the
   corresponding working LSP (known as a secondary LSP <span>[<a href="#RFC4872" class="xref">RFC4872</a>]</span>).
   Whether to establish it before or after failure is according
   to operator choice or policy.<a href="#section-1-6" class="pilcrow">¶</a></p>
<p id="section-1-7"><span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span> introduces a generic mechanism to
   create a grouping of LSPs, which can then be used to define
   associations between a set of LSPs.  The mechanism is equally
   applicable to stateful PCE (active and passive modes) and stateless
   PCE.<a href="#section-1-7" class="pilcrow">¶</a></p>
<p id="section-1-8">This document specifies a PCEP extension to associate one working LSP with one or more
   protection LSPs using the generic association mechanism.<a href="#section-1-8" class="pilcrow">¶</a></p>
<p id="section-1-9">This document describes a PCEP
   extension to associate protection LSPs by creating the Path Protection Association Group (PPAG)
   and encoding this association in PCEP messages for stateful PCEP
   sessions.<a href="#section-1-9" class="pilcrow">¶</a></p>
<section id="section-1.1">
        <h3 id="name-requirements-language">
<a href="#section-1.1" class="section-number selfRef">1.1. </a><a href="#name-requirements-language" class="section-name selfRef">Requirements Language</a>
        </h3>
<p id="section-1.1-1">
    The key words "<span class="bcp14">MUST</span>", "<span class="bcp14">MUST NOT</span>", "<span class="bcp14">REQUIRED</span>", "<span class="bcp14">SHALL</span>", "<span class="bcp14">SHALL NOT</span>", "<span class="bcp14">SHOULD</span>", "<span class="bcp14">SHOULD NOT</span>", "<span class="bcp14">RECOMMENDED</span>", "<span class="bcp14">NOT RECOMMENDED</span>",
    "<span class="bcp14">MAY</span>", and "<span class="bcp14">OPTIONAL</span>" in this document are to be interpreted as
    described in BCP 14 <span>[<a href="#RFC2119" class="xref">RFC2119</a>]</span> <span>[<a href="#RFC8174" class="xref">RFC8174</a>]</span> 
    when, and only when, they appear in all capitals, as shown here.<a href="#section-1.1-1" class="pilcrow">¶</a></p>
</section>
</section>
<section id="section-2">
      <h2 id="name-terminology">
<a href="#section-2" class="section-number selfRef">2. </a><a href="#name-terminology" class="section-name selfRef">Terminology</a>
      </h2>
<p id="section-2-1">The following terms are used in this document:<a href="#section-2-1" class="pilcrow">¶</a></p>
<ul class="ulEmpty">
<li class="ulEmpty" id="section-2-2.1">
          <dl class="dlParallel" id="section-2-2.1.1">
            <dt id="section-2-2.1.1.1">ERO:</dt>
<dd id="section-2-2.1.1.2"> Explicit Route Object<a href="#section-2-2.1.1.2" class="pilcrow">¶</a>
</dd>
<dt id="section-2-2.1.1.3">LSP:</dt>
<dd id="section-2-2.1.1.4"> Label Switched Path<a href="#section-2-2.1.1.4" class="pilcrow">¶</a>
</dd>
<dt id="section-2-2.1.1.5">PCC:</dt>
<dd id="section-2-2.1.1.6"> Path Computation Client<a href="#section-2-2.1.1.6" class="pilcrow">¶</a>
</dd>
<dt id="section-2-2.1.1.7">PCE:</dt>
<dd id="section-2-2.1.1.8"> Path Computation Element<a href="#section-2-2.1.1.8" class="pilcrow">¶</a>
</dd>
<dt id="section-2-2.1.1.9">PCEP:</dt>
<dd id="section-2-2.1.1.10"> Path Computation Element Communication Protocol<a href="#section-2-2.1.1.10" class="pilcrow">¶</a>
</dd>
<dt id="section-2-2.1.1.11">PPAG:</dt>
<dd id="section-2-2.1.1.12"> Path Protection Association Group<a href="#section-2-2.1.1.12" class="pilcrow">¶</a>
</dd>
<dt id="section-2-2.1.1.13">TLV:</dt>
<dd id="section-2-2.1.1.14"> Type, Length, and Value<a href="#section-2-2.1.1.14" class="pilcrow">¶</a>
</dd>
</dl>
</li>
</ul>
</section>
<div id="Extension-Overview">
<section id="section-3">
      <h2 id="name-pcep-extensions">
<a href="#section-3" class="section-number selfRef">3. </a><a href="#name-pcep-extensions" class="section-name selfRef">PCEP Extensions</a>
      </h2>
<div id="Path-Protection-Association-Type">
<section id="section-3.1">
        <h3 id="name-path-protection-association">
<a href="#section-3.1" class="section-number selfRef">3.1. </a><a href="#name-path-protection-association" class="section-name selfRef">Path Protection Association Type</a>
        </h3>
<p id="section-3.1-1">As per <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span>, LSPs are not associated by listing the other LSPs
        with which they interact but, rather, by making them belong to an
        association group. All LSPs join an association group
        individually. The generic ASSOCIATION object is used to associate two
        or more LSPs as specified in <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span>. This
        document defines a new Association type called "Path Protection
        Association Type" of value 1 and a "Path Protection Association
        Group" (PPAG).  A member LSP of a PPAG can take the role of working or
        protection LSP.  A PPAG can have one working LSP and/or one or more
        protection LSPs. The source, destination, Tunnel ID (as carried in
        LSP-IDENTIFIERS TLV <span>[<a href="#RFC8231" class="xref">RFC8231</a>]</span>, with
        description as per <span>[<a href="#RFC3209" class="xref">RFC3209</a>]</span>), and
        Protection Type (PT) (in Path Protection Association TLV) of all LSPs
        within a PPAG <span class="bcp14">MUST</span> be the same. As per <span>[<a href="#RFC3209" class="xref">RFC3209</a>]</span>, a TE tunnel is used to associate a
        set of LSPs during reroute or to spread a traffic trunk over multiple
        paths.<a href="#section-3.1-1" class="pilcrow">¶</a></p>
<p id="section-3.1-2">The format of the ASSOCIATION object used for PPAG is specified in 
<span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span>.<a href="#section-3.1-2" class="pilcrow">¶</a></p>
<p id="section-3.1-3"><span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span> specifies the mechanism for the
   capability advertisement of the Association types supported by a PCEP
   speaker by defining an ASSOC-Type-List TLV to be carried within an
   OPEN object.  This capability exchange for the Association type
   described in this document (i.e.,  Path Protection Association Type) <span class="bcp14">MAY</span> be
   done before using this association, i.e., the PCEP speaker <span class="bcp14">MAY</span>
   include the Path Protection Association Type (1) in the ASSOC-Type-List TLV
   before using the PPAG in the PCEP messages.<a href="#section-3.1-3" class="pilcrow">¶</a></p>
<p id="section-3.1-4">This Association type is dynamic in nature and created by the PCC
        or PCE for the LSPs belonging to the same TE tunnel (as described in
        <span>[<a href="#RFC3209" class="xref">RFC3209</a>]</span>) originating at the same
        head node and terminating at the same destination.  These associations
        are conveyed via PCEP messages to the PCEP peer. As per <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span>, the
        association source is set to the local PCEP speaker address that
        created the association unless local policy dictates
        otherwise. Operator-configured Association Range <span class="bcp14">MUST NOT</span> be set for this Association type and <span class="bcp14">MUST</span>
        be ignored.<a href="#section-3.1-4" class="pilcrow">¶</a></p>
</section>
</div>
<div id="Path-Protection-Association-TLV">
<section id="section-3.2">
        <h3 id="name-path-protection-association-">
<a href="#section-3.2" class="section-number selfRef">3.2. </a><a href="#name-path-protection-association-" class="section-name selfRef">Path Protection Association TLV</a>
        </h3>
<p id="section-3.2-1">The Path Protection Association TLV is an optional TLV for use in
        the ASSOCIATION object with the Path Protection Association Type. The
        Path Protection Association TLV <span class="bcp14">MUST NOT</span> be present
        more than once.  If it appears more than once, only the first
        occurrence is processed and any others <span class="bcp14">MUST</span> be
        ignored.<a href="#section-3.2-1" class="pilcrow">¶</a></p>
<p id="section-3.2-2"> The Path Protection Association TLV follows the PCEP TLV format of
 <span>[<a href="#RFC5440" class="xref">RFC5440</a>]</span>.<a href="#section-3.2-2" class="pilcrow">¶</a></p>
<p id="section-3.2-3"> The Type (16 bits) of the TLV is 38. The Length 
field (16 bits) has a fixed value of 4.<a href="#section-3.2-3" class="pilcrow">¶</a></p>
<p id="section-3.2-4">The value is comprised of a single field, the Path Protection Association
   Flags (32 bits), where each bit represents a flag option.<a href="#section-3.2-4" class="pilcrow">¶</a></p>
<p id="section-3.2-5"> The format of the Path Protection Association TLV (<a href="#PPAG-TLV-Fmt" class="xref">Figure 1</a>) is as
        follows:<a href="#section-3.2-5" class="pilcrow">¶</a></p>
<span id="name-path-protection-association-t"></span><div id="PPAG-TLV-Fmt">
<figure id="figure-1">
          <div class="artwork art-text alignLeft" id="section-3.2-6.1">
<pre>
   0                   1                   2                   3
   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |         Type = 38             |            Length = 4         |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |   PT      |               Unassigned Flags                |S|P|
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+</pre>
</div>
<figcaption><a href="#figure-1" class="selfRef">Figure 1</a>:
<a href="#name-path-protection-association-t" class="selfRef">Path Protection Association TLV Format</a>
          </figcaption></figure>
</div>
<p id="section-3.2-7">Path Protection Association Flags (32 bits)<a href="#section-3.2-7" class="pilcrow">¶</a></p>
<p id="section-3.2-8">The following flags are currently defined:<a href="#section-3.2-8" class="pilcrow">¶</a></p>
<ul>
<li id="section-3.2-9.1">Protecting (P): 1 bit - This bit is as defined in <span><a href="https://www.rfc-editor.org/rfc/rfc4872#section-14.1" class="relref">Section 14.1</a> of [<a href="#RFC4872" class="xref">RFC4872</a>]</span> to indicate if
          the LSP is a working (0) or protection (1) LSP.<a href="#section-3.2-9.1" class="pilcrow">¶</a>
</li>
<li id="section-3.2-9.2">Secondary (S): 1 bit - This bit is as defined in <span><a href="https://www.rfc-editor.org/rfc/rfc4872#section-14.1" class="relref">Section 14.1</a> of [<a href="#RFC4872" class="xref">RFC4872</a>]</span> to indicate if
          the LSP is a primary (0) or secondary (1) LSP. The S flag is ignored
          if the P flag is not set.<a href="#section-3.2-9.2" class="pilcrow">¶</a>
</li>
<li id="section-3.2-9.3">Protection Type (PT): 6 bits - This field is as defined in <span><a href="https://www.rfc-editor.org/rfc/rfc4872#section-14.1" class="relref">Section 14.1</a> of [<a href="#RFC4872" class="xref">RFC4872</a>]</span> (as "LSP
          (Protection Type) Flags") to indicate the LSP protection type in
          use. Any type already defined or that could be defined in the future
          for use in the RSVP-TE PROTECTION object is acceptable in this TLV
          unless explicitly stated otherwise.<a href="#section-3.2-9.3" class="pilcrow">¶</a>
</li>
<li id="section-3.2-9.4">Unassigned bits are considered reserved.  They <span class="bcp14">MUST</span> be set to 0 on
   transmission and <span class="bcp14">MUST</span> be ignored on receipt.<a href="#section-3.2-9.4" class="pilcrow">¶</a>
</li>
</ul>
<p id="section-3.2-10">If the TLV is missing in the PPAG ASSOCIATION object, it is
        considered that the LSP is a working LSP (i.e., as if the P bit is
        unset).<a href="#section-3.2-10" class="pilcrow">¶</a></p>
</section>
</div>
</section>
</div>
<div id="Operation">
<section id="section-4">
      <h2 id="name-operation">
<a href="#section-4" class="section-number selfRef">4. </a><a href="#name-operation" class="section-name selfRef">Operation</a>
      </h2>
<p id="section-4-1">An LSP is associated with
   other LSPs with which it interacts by adding them to a common
   association group via the ASSOCIATION object. All procedures and error handling for the ASSOCIATION 
   object is as per <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span>.<a href="#section-4-1" class="pilcrow">¶</a></p>
<div id="Operation-State-Sync">
<section id="section-4.1">
        <h3 id="name-state-synchronization">
<a href="#section-4.1" class="section-number selfRef">4.1. </a><a href="#name-state-synchronization" class="section-name selfRef">State Synchronization</a>
        </h3>
<p id="section-4.1-1">During state synchronization, a PCC reports all the existing LSP states as described in <span>[<a href="#RFC8231" class="xref">RFC8231</a>]</span>.
   The association group membership pertaining to an LSP is also reported as per <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span>. This
   includes PPAGs.<a href="#section-4.1-1" class="pilcrow">¶</a></p>
</section>
</div>
<div id="Operation-PCC-Init">
<section id="section-4.2">
        <h3 id="name-pcc-initiated-lsps">
<a href="#section-4.2" class="section-number selfRef">4.2. </a><a href="#name-pcc-initiated-lsps" class="section-name selfRef">PCC-Initiated LSPs</a>
        </h3>
<p id="section-4.2-1">A PCC can associate a set of LSPs under its control for path
        protection purposes. Similarly, the PCC can remove one or more LSPs
        under its control from the corresponding PPAG. In both cases, the PCC
        reports the change in association to PCE(s) via a Path Computation
        Report (PCRpt) message. A PCC can also delegate the working and
        protection LSPs to an active stateful PCE, where the PCE would control
        the LSPs. The stateful PCE could update the paths and attributes of
        the LSPs in the association group via a Path Computation Update (PCUpd)
        message. A PCE could also update the association to the PCC via a PCUpd
        message. These procedures are described in <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span>.<a href="#section-4.2-1" class="pilcrow">¶</a></p>
<p id="section-4.2-2">It is expected that both working and protection LSPs are delegated together (and to the same PCE) to avoid any race conditions. Refer to <span>[<a href="#I-D.litkowski-pce-state-sync" class="xref">STATE-PCE-SYNC</a>]</span> for the problem description.<a href="#section-4.2-2" class="pilcrow">¶</a></p>
</section>
</div>
<div id="Operation-PCE-Init">
<section id="section-4.3">
        <h3 id="name-pce-initiated-lsps">
<a href="#section-4.3" class="section-number selfRef">4.3. </a><a href="#name-pce-initiated-lsps" class="section-name selfRef">PCE-Initiated LSPs</a>
        </h3>
<p id="section-4.3-1">A PCE can create/update working and protection LSPs independently. 
    As specified in <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span>, 
    Association Groups can be created by both the PCE and the PCC. 
    Furthermore, a PCE can remove a protection LSP from a PPAG as specified in 
    <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span>. The PCE uses PCUpd 
    or Path Computation Initiate (PCInitiate) messages to communicate the association information to the PCC.<a href="#section-4.3-1" class="pilcrow">¶</a></p>
</section>
</div>
<div id="Session-Termination">
<section id="section-4.4">
        <h3 id="name-session-termination">
<a href="#section-4.4" class="section-number selfRef">4.4. </a><a href="#name-session-termination" class="section-name selfRef">Session Termination</a>
        </h3>
<p id="section-4.4-1">As per <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span>, the association information is cleared along with
        the LSP state information.  When a PCEP session is terminated, after
        expiry of State Timeout Interval at the PCC, the LSP state associated
        with that PCEP session is reverted to operator-defined default
        parameters or behaviors as per <span>[<a href="#RFC8231" class="xref">RFC8231</a>]</span>. The same procedure is also followed for the
        association information.  On session termination at the PCE, when the
        LSP state reported by PCC is cleared, the association information is
        also cleared as per <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span>.  Where there are no LSPs in an association group,
        the association is considered to be deleted.<a href="#section-4.4-1" class="pilcrow">¶</a></p>
</section>
</div>
<div id="Operation-Error-Handling">
<section id="section-4.5">
        <h3 id="name-error-handling">
<a href="#section-4.5" class="section-number selfRef">4.5. </a><a href="#name-error-handling" class="section-name selfRef">Error Handling</a>
        </h3>
<p id="section-4.5-1">As per the processing rules specified in <span><a href="https://www.rfc-editor.org/rfc/rfc8697#section-6.4" class="relref">Section 6.4</a> of [<a href="#RFC8697" class="xref">RFC8697</a>]</span>, if a PCEP speaker does not support this Path
        Protection Association Type, it would return a PCErr message with
        Error-Type 26 "Association Error" and Error-Value 1 "Association type
        is not supported".<a href="#section-4.5-1" class="pilcrow">¶</a></p>
<p id="section-4.5-2">All LSPs (working or protection) within a PPAG <span class="bcp14">MUST</span>
        belong to the same TE tunnel (as described in <span>[<a href="#RFC3209" class="xref">RFC3209</a>]</span>) and have the same source and destination.  If a
        PCEP speaker attempts to add or update an LSP to a PPAG and the Tunnel
        ID (as carried in the LSP-IDENTIFIERS TLV <span>[<a href="#RFC8231" class="xref">RFC8231</a>]</span>, with a description as per <span>[<a href="#RFC3209" class="xref">RFC3209</a>]</span>) or source or destination of the LSP is different
        from the LSP(s) in the PPAG, the PCEP speaker <span class="bcp14">MUST</span> send
        PCErr with Error-Type 26 (Association Error) <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span> and
        Error-Value 9 (Tunnel ID or endpoints mismatch for Path Protection
        Association). In case of Path Protection, an LSP-IDENTIFIERS TLV
        <span class="bcp14">SHOULD</span> be included for all LSPs (including Segment
        Routing (SR) <span>[<a href="#RFC8664" class="xref">RFC8664</a>]</span>). If the Protection Type (PT) (in the Path Protection
        Association TLV) is different from the LSPs in the PPAG, the PCEP
        speaker <span class="bcp14">MUST</span> send PCErr with Error-Type 26 (Association
        Error) <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span> and Error-Value 6 (Association information
        mismatch) as per <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span>.<a href="#section-4.5-2" class="pilcrow">¶</a></p>
<p id="section-4.5-3">When the PCEP peer does not support the protection type set in PPAG, the PCEP peer <span class="bcp14">MUST</span> send PCErr with Error-Type 26 (Association Error) 
  <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span> and Error-Value 11 (Protection type is not supported).<a href="#section-4.5-3" class="pilcrow">¶</a></p>
<p id="section-4.5-4">A given LSP <span class="bcp14">MAY</span> belong to more than one PPAG. If there is a conflict between any of the two PPAGs, the PCEP peer <span class="bcp14">MUST</span> send PCErr with Error-Type 26 (Association Error) <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span> and Error-Value 6 (Association information mismatch) as per <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span>.<a href="#section-4.5-4" class="pilcrow">¶</a></p>
<p id="section-4.5-5">When the protection type is set to 1+1 (i.e., protection type=0x08
        or 0x10), there <span class="bcp14">MUST</span> be at maximum only one working LSP
        and one protection LSP within a PPAG.  If a PCEP speaker attempts to
        add another working/protection LSP, the PCEP peer <span class="bcp14">MUST</span>
        send PCErr with Error-Type 26 (Association Error) <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span> and Error-Value 10 (Attempt to add
        another working/protection LSP for Path Protection Association).<a href="#section-4.5-5" class="pilcrow">¶</a></p>
<p id="section-4.5-6">When the protection type is set to 1:N (i.e., protection
        type=0x04), there <span class="bcp14">MUST</span> be at maximum only one protection
        LSP, and the number of working LSPs <span class="bcp14">MUST NOT</span> be more
        than N within a PPAG. If a PCEP speaker attempts to add another
        working/protection LSP, the PCEP peer <span class="bcp14">MUST</span> send PCErr
        with Error-Type 26 (Association Error) <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span> and Error-Value 10 (Attempt to add another
        working/protection LSP for Path Protection Association).<a href="#section-4.5-6" class="pilcrow">¶</a></p>
<p id="section-4.5-7">During the make-before-break (MBB) procedure, two paths will
        briefly coexist. The error handling related to the number of LSPs allowed
        in a PPAG <span class="bcp14">MUST NOT</span> be applied during MBB.<a href="#section-4.5-7" class="pilcrow">¶</a></p>
<p id="section-4.5-8">All processing as per <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span> continues to apply.<a href="#section-4.5-8" class="pilcrow">¶</a></p>
</section>
</div>
</section>
</div>
<section id="section-5">
      <h2 id="name-other-considerations">
<a href="#section-5" class="section-number selfRef">5. </a><a href="#name-other-considerations" class="section-name selfRef">Other Considerations</a>
      </h2>
<p id="section-5-1">The working and protection LSPs are typically resource disjoint
      (e.g., node, Shared Risk Link Group [SRLG] disjoint).  This ensures that
      a single failure will not affect both the working and protection
      LSPs. The disjoint requirement for a group of LSPs is handled via
      another Association type called "Disjointness Association" as described
      in <span>[<a href="#I-D.ietf-pce-association-diversity" class="xref">PCEP-LSP-EXT</a>]</span>.
      The diversity requirements for the protection LSP are also handled by
      including both ASSOCIATION objects identifying both the protection
      association group and the disjoint association group for the group of
      LSPs. The relationship between the Synchronization VECtor (SVEC) object
      and the Disjointness Association is described in <span><a href="https://tools.ietf.org/html/draft-ietf-pce-association-diversity-14#section-5.4" class="relref">Section 5.4</a> of [<a href="#I-D.ietf-pce-association-diversity" class="xref">PCEP-LSP-EXT</a>]</span>.<a href="#section-5-1" class="pilcrow">¶</a></p>
<p id="section-5-2"><span>[<a href="#RFC4872" class="xref">RFC4872</a>]</span> introduces the concept and
      mechanisms to support the association of one LSP to another LSP across
      different RSVP Traffic Engineering (RSVP-TE) sessions using the ASSOCIATION
      and PROTECTION object.  The information in the Path Protection
      Association TLV in PCEP as received from the PCE is used to trigger the
      signaling of the working LSP and protection LSP, with the Path Protection
      Association Flags mapped to the corresponding fields in the PROTECTION
      object in RSVP-TE.<a href="#section-5-2" class="pilcrow">¶</a></p>
</section>
<section id="section-6">
      <h2 id="name-iana-considerations">
<a href="#section-6" class="section-number selfRef">6. </a><a href="#name-iana-considerations" class="section-name selfRef">IANA Considerations</a>
      </h2>
<section id="section-6.1">
        <h3 id="name-association-type">
<a href="#section-6.1" class="section-number selfRef">6.1. </a><a href="#name-association-type" class="section-name selfRef">Association Type</a>
        </h3>
<p id="section-6.1-1">This document defines a new Association type, originally
    defined in <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span>, for path protection. 
    IANA has assigned new value in the
    "ASSOCIATION Type Field" subregistry (created by <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span>) as follows:<a href="#section-6.1-1" class="pilcrow">¶</a></p>
<span id="name-association-type-field"></span><table class="center" id="table-1">
          <caption>
<a href="#table-1" class="selfRef">Table 1</a>:
<a href="#name-association-type-field" class="selfRef">ASSOCIATION Type Field</a>
          </caption>
<thead>
            <tr>
              <th class="text-left" rowspan="1" colspan="1">Type</th>
              <th class="text-left" rowspan="1" colspan="1">Name</th>
              <th class="text-left" rowspan="1" colspan="1">Reference</th>
            </tr>
          </thead>
          <tbody>
            <tr>
              <td class="text-left" rowspan="1" colspan="1">1</td>
              <td class="text-left" rowspan="1" colspan="1">Path Protection Association</td>
              <td class="text-left" rowspan="1" colspan="1">RFC 8745</td>
            </tr>
          </tbody>
        </table>
</section>
<section id="section-6.2">
        <h3 id="name-path-protection-association-tl">
<a href="#section-6.2" class="section-number selfRef">6.2. </a><a href="#name-path-protection-association-tl" class="section-name selfRef">Path Protection Association TLV</a>
        </h3>
<p id="section-6.2-1"> This document defines a new TLV for carrying the additional information of LSPs within a path protection association group.
      IANA has assigned a new value in the
   "PCEP TLV Type Indicators" subregistry as follows:<a href="#section-6.2-1" class="pilcrow">¶</a></p>
<span id="name-pcep-tlv-type-indicators"></span><table class="center" id="table-2">
          <caption>
<a href="#table-2" class="selfRef">Table 2</a>:
<a href="#name-pcep-tlv-type-indicators" class="selfRef">PCEP TLV Type Indicators</a>
          </caption>
<thead>
            <tr>
              <th class="text-left" rowspan="1" colspan="1">Value</th>
              <th class="text-left" rowspan="1" colspan="1">Description</th>
              <th class="text-left" rowspan="1" colspan="1">Reference</th>
            </tr>
          </thead>
          <tbody>
            <tr>
              <td class="text-left" rowspan="1" colspan="1">38</td>
              <td class="text-left" rowspan="1" colspan="1">Path Protection Association Group TLV</td>
              <td class="text-left" rowspan="1" colspan="1">RFC 8745</td>
            </tr>
          </tbody>
        </table>
<p id="section-6.2-3"> Per this document, a new subregistry named "Path
        protection Association Group TLV Flag Field" has been created within the
        "Path Computation Element Protocol (PCEP) Numbers" registry to manage
        the Flag field in the Path Protection Association Group TLV.  New
        values are to be assigned by Standards Action <span>[<a href="#RFC8126" class="xref">RFC8126</a>]</span>.  Each bit should be tracked with the following
        qualities:<a href="#section-6.2-3" class="pilcrow">¶</a></p>
<ul>
<li id="section-6.2-4.1">Bit number (count from 0 as the most significant bit)<a href="#section-6.2-4.1" class="pilcrow">¶</a>
</li>
<li id="section-6.2-4.2">Name of the flag<a href="#section-6.2-4.2" class="pilcrow">¶</a>
</li>
<li id="section-6.2-4.3">Reference<a href="#section-6.2-4.3" class="pilcrow">¶</a>
</li>
</ul>
<span id="name-path-protection-association-g"></span><div id="PPAG-TLV-Table-IANA">
<table class="center" id="table-3">
          <caption>
<a href="#table-3" class="selfRef">Table 3</a>:
<a href="#name-path-protection-association-g" class="selfRef">Path Protection Association Group TLV Flag Field</a>
          </caption>
<thead>
            <tr>
              <th class="text-center" rowspan="1" colspan="1">Bit</th>
              <th class="text-center" rowspan="1" colspan="1">Name</th>
              <th class="text-center" rowspan="1" colspan="1">Reference</th>
            </tr>
          </thead>
          <tbody>
            <tr>
              <td class="text-center" rowspan="1" colspan="1">31</td>
              <td class="text-center" rowspan="1" colspan="1">P - PROTECTION-LSP</td>
              <td class="text-center" rowspan="1" colspan="1">RFC 8745 </td>
            </tr>
            <tr>
              <td class="text-center" rowspan="1" colspan="1">30</td>
              <td class="text-center" rowspan="1" colspan="1">S - SECONDARY-LSP</td>
              <td class="text-center" rowspan="1" colspan="1">RFC 8745</td>
            </tr>
            <tr>
              <td class="text-center" rowspan="1" colspan="1">6-29</td>
              <td class="text-center" rowspan="1" colspan="1">Unassigned</td>
              <td class="text-center" rowspan="1" colspan="1">RFC 8745</td>
            </tr>
            <tr>
              <td class="text-center" rowspan="1" colspan="1">0-5</td>
              <td class="text-center" rowspan="1" colspan="1">Protection Type Flags</td>
              <td class="text-center" rowspan="1" colspan="1">RFC 8745 </td>
            </tr>
          </tbody>
        </table>
</div>
</section>
<section id="section-6.3">
        <h3 id="name-pcep-errors">
<a href="#section-6.3" class="section-number selfRef">6.3. </a><a href="#name-pcep-errors" class="section-name selfRef">PCEP Errors</a>
        </h3>
<p id="section-6.3-1">This document defines new Error-Values related to path protection
        association for Error-type 26 "Association Error" defined in <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span>.  IANA has allocated new error values within the "PCEP-ERROR Object
        Error Types and Values" subregistry of the PCEP Numbers registry as
        follows:<a href="#section-6.3-1" class="pilcrow">¶</a></p>
<span id="name-pcep-error-object-error-typ"></span><table class="center" id="table-4">
          <caption>
<a href="#table-4" class="selfRef">Table 4</a>:
<a href="#name-pcep-error-object-error-typ" class="selfRef">PCEP-ERROR Object Error Types and Values</a>
          </caption>
<thead>
            <tr>
              <th class="text-left" rowspan="1" colspan="1"> Error-Type </th>
              <th class="text-left" rowspan="1" colspan="1"> Meaning </th>
              <th class="text-left" rowspan="1" colspan="1"> Error-value </th>
              <th class="text-left" rowspan="1" colspan="1"> Reference </th>
            </tr>
          </thead>
          <tbody>
            <tr>
              <td class="text-left" rowspan="1" colspan="1"> 26 </td>
              <td class="text-left" rowspan="1" colspan="1">Association Error</td>
              <td class="text-left" rowspan="1" colspan="1"></td>
              <td class="text-left" rowspan="1" colspan="1">
                <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span>
</td>
            </tr>
            <tr>
              <td class="text-left" rowspan="1" colspan="1"></td>
              <td class="text-left" rowspan="1" colspan="1"></td>
              <td class="text-left" rowspan="1" colspan="1">9: Tunnel ID or endpoints mismatch for Path Protection Association</td>
              <td class="text-left" rowspan="1" colspan="1">RFC 8745</td>
            </tr>
            <tr>
              <td class="text-left" rowspan="1" colspan="1"></td>
              <td class="text-left" rowspan="1" colspan="1"></td>
              <td class="text-left" rowspan="1" colspan="1">10: Attempt to add another working/protection LSP for Path Protection Association</td>
              <td class="text-left" rowspan="1" colspan="1">RFC 8745</td>
            </tr>
            <tr>
              <td class="text-left" rowspan="1" colspan="1"></td>
              <td class="text-left" rowspan="1" colspan="1"></td>
              <td class="text-left" rowspan="1" colspan="1">11: Protection type is not supported</td>
              <td class="text-left" rowspan="1" colspan="1">RFC 8745</td>
            </tr>
          </tbody>
        </table>
</section>
</section>
<section id="section-7">
      <h2 id="name-security-considerations">
<a href="#section-7" class="section-number selfRef">7. </a><a href="#name-security-considerations" class="section-name selfRef">Security Considerations</a>
      </h2>
<p id="section-7-1">
               The security considerations described in <span>[<a href="#RFC8231" class="xref">RFC8231</a>]</span>, <span>[<a href="#RFC8281" class="xref">RFC8281</a>]</span>,
               and <span>[<a href="#RFC5440" class="xref">RFC5440</a>]</span> apply to the
               extensions described in this document as well.  Additional
               considerations related to associations where a malicious PCEP
               speaker could be spoofed and could be used as an attack vector
               by creating associations are described in <span>[<a href="#RFC8697" class="xref">RFC8697</a>]</span>.
               Adding a spurious protection LSP to the Path Protection
               Association group could give a false sense of network
               reliability, which leads to issues when the working LSP is down
               and the protection LSP fails as well. Thus, securing the PCEP
               session using Transport Layer Security (TLS) <span>[<a href="#RFC8253" class="xref">RFC8253</a>]</span>, as per the recommendations
               and best current practices in BCP 195 <span>[<a href="#RFC7525" class="xref">RFC7525</a>]</span>, is <span class="bcp14">RECOMMENDED</span>.<a href="#section-7-1" class="pilcrow">¶</a></p>
</section>
<section id="section-8">
      <h2 id="name-manageability-consideration">
<a href="#section-8" class="section-number selfRef">8. </a><a href="#name-manageability-consideration" class="section-name selfRef">Manageability Considerations</a>
      </h2>
<section id="section-8.1">
        <h3 id="name-control-of-function-and-pol">
<a href="#section-8.1" class="section-number selfRef">8.1. </a><a href="#name-control-of-function-and-pol" class="section-name selfRef">Control of Function and Policy</a>
        </h3>
<p id="section-8.1-1">Mechanisms defined in this document do not imply any control or policy 
            requirements in addition to those already listed in
        <span>[<a href="#RFC5440" class="xref">RFC5440</a>]</span>, <span>[<a href="#RFC8231" class="xref">RFC8231</a>]</span>, and 
        <span>[<a href="#RFC8281" class="xref">RFC8281</a>]</span>.<a href="#section-8.1-1" class="pilcrow">¶</a></p>
</section>
<section id="section-8.2">
        <h3 id="name-information-and-data-models">
<a href="#section-8.2" class="section-number selfRef">8.2. </a><a href="#name-information-and-data-models" class="section-name selfRef">Information and Data Models</a>
        </h3>
<p id="section-8.2-1"><span>[<a href="#RFC7420" class="xref">RFC7420</a>]</span> describes the PCEP MIB; there are no new MIB Objects
        for this document.<a href="#section-8.2-1" class="pilcrow">¶</a></p>
<p id="section-8.2-2">The PCEP YANG module <span>[<a href="#I-D.ietf-pce-pcep-yang" class="xref">PCEP-YANG</a>]</span> supports
        associations.<a href="#section-8.2-2" class="pilcrow">¶</a></p>
</section>
<section id="section-8.3">
        <h3 id="name-liveness-detection-and-moni">
<a href="#section-8.3" class="section-number selfRef">8.3. </a><a href="#name-liveness-detection-and-moni" class="section-name selfRef">Liveness Detection and Monitoring</a>
        </h3>
<p id="section-8.3-1">Mechanisms defined in this document do not imply any new liveness detection
        and monitoring requirements in addition to those already listed in
        <span>[<a href="#RFC5440" class="xref">RFC5440</a>]</span>, <span>[<a href="#RFC8231" class="xref">RFC8231</a>]</span>, and 
        <span>[<a href="#RFC8281" class="xref">RFC8281</a>]</span>.<a href="#section-8.3-1" class="pilcrow">¶</a></p>
</section>
<section id="section-8.4">
        <h3 id="name-verify-correct-operations">
<a href="#section-8.4" class="section-number selfRef">8.4. </a><a href="#name-verify-correct-operations" class="section-name selfRef">Verify Correct Operations</a>
        </h3>
<p id="section-8.4-1">Mechanisms defined in this document do not imply any new operation
        verification requirements in addition to those already listed in
        <span>[<a href="#RFC5440" class="xref">RFC5440</a>]</span>, <span>[<a href="#RFC8231" class="xref">RFC8231</a>]</span>, and 
        <span>[<a href="#RFC8281" class="xref">RFC8281</a>]</span>.<a href="#section-8.4-1" class="pilcrow">¶</a></p>
</section>
<section id="section-8.5">
        <h3 id="name-requirements-on-other-proto">
<a href="#section-8.5" class="section-number selfRef">8.5. </a><a href="#name-requirements-on-other-proto" class="section-name selfRef">Requirements on Other Protocols</a>
        </h3>
<p id="section-8.5-1">Mechanisms defined in this document do not imply any new requirements
        on other protocols.<a href="#section-8.5-1" class="pilcrow">¶</a></p>
</section>
<section id="section-8.6">
        <h3 id="name-impact-on-network-operation">
<a href="#section-8.6" class="section-number selfRef">8.6. </a><a href="#name-impact-on-network-operation" class="section-name selfRef">Impact on Network Operations</a>
        </h3>
<p id="section-8.6-1">Mechanisms defined in this document do not have any impact on
        network operations in addition to those already listed in
        <span>[<a href="#RFC5440" class="xref">RFC5440</a>]</span>, <span>[<a href="#RFC8231" class="xref">RFC8231</a>]</span>, and 
        <span>[<a href="#RFC8281" class="xref">RFC8281</a>]</span>.<a href="#section-8.6-1" class="pilcrow">¶</a></p>
</section>
</section>
<section id="section-9">
      <h2 id="name-references">
<a href="#section-9" class="section-number selfRef">9. </a><a href="#name-references" class="section-name selfRef">References</a>
      </h2>
<section id="section-9.1">
        <h3 id="name-normative-references">
<a href="#section-9.1" class="section-number selfRef">9.1. </a><a href="#name-normative-references" class="section-name selfRef">Normative References</a>
        </h3>
<dl class="references">
<dt id="RFC2119">[RFC2119]</dt>
<dd>
<span class="refAuthor">Bradner, S.</span>, <span class="refTitle">"Key words for use in RFCs to Indicate Requirement Levels"</span>, <span class="seriesInfo">BCP 14</span>, <span class="seriesInfo">RFC 2119</span>, <span class="seriesInfo">DOI 10.17487/RFC2119</span>, <time datetime="1997-03">March 1997</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc2119">https://www.rfc-editor.org/info/rfc2119</a>&gt;</span>. </dd>
<dt id="RFC3209">[RFC3209]</dt>
<dd>
<span class="refAuthor">Awduche, D.</span><span class="refAuthor">, Berger, L.</span><span class="refAuthor">, Gan, D.</span><span class="refAuthor">, Li, T.</span><span class="refAuthor">, Srinivasan, V.</span><span class="refAuthor">, and G. Swallow</span>, <span class="refTitle">"RSVP-TE: Extensions to RSVP for LSP Tunnels"</span>, <span class="seriesInfo">RFC 3209</span>, <span class="seriesInfo">DOI 10.17487/RFC3209</span>, <time datetime="2001-12">December 2001</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc3209">https://www.rfc-editor.org/info/rfc3209</a>&gt;</span>. </dd>
<dt id="RFC4872">[RFC4872]</dt>
<dd>
<span class="refAuthor">Lang, J.P., Ed.</span><span class="refAuthor">, Rekhter, Y., Ed.</span><span class="refAuthor">, and D. Papadimitriou, Ed.</span>, <span class="refTitle">"RSVP-TE Extensions in Support of End-to-End Generalized Multi-Protocol Label Switching (GMPLS) Recovery"</span>, <span class="seriesInfo">RFC 4872</span>, <span class="seriesInfo">DOI 10.17487/RFC4872</span>, <time datetime="2007-05">May 2007</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc4872">https://www.rfc-editor.org/info/rfc4872</a>&gt;</span>. </dd>
<dt id="RFC5440">[RFC5440]</dt>
<dd>
<span class="refAuthor">Vasseur, JP., Ed.</span><span class="refAuthor"> and JL. Le Roux, Ed.</span>, <span class="refTitle">"Path Computation Element (PCE) Communication Protocol (PCEP)"</span>, <span class="seriesInfo">RFC 5440</span>, <span class="seriesInfo">DOI 10.17487/RFC5440</span>, <time datetime="2009-03">March 2009</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc5440">https://www.rfc-editor.org/info/rfc5440</a>&gt;</span>. </dd>
<dt id="RFC7525">[RFC7525]</dt>
<dd>
<span class="refAuthor">Sheffer, Y.</span><span class="refAuthor">, Holz, R.</span><span class="refAuthor">, and P. Saint-Andre</span>, <span class="refTitle">"Recommendations for Secure Use of Transport Layer Security (TLS) and Datagram Transport Layer Security (DTLS)"</span>, <span class="seriesInfo">BCP 195</span>, <span class="seriesInfo">RFC 7525</span>, <span class="seriesInfo">DOI 10.17487/RFC7525</span>, <time datetime="2015-05">May 2015</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc7525">https://www.rfc-editor.org/info/rfc7525</a>&gt;</span>. </dd>
<dt id="RFC8126">[RFC8126]</dt>
<dd>
<span class="refAuthor">Cotton, M.</span><span class="refAuthor">, Leiba, B.</span><span class="refAuthor">, and T. Narten</span>, <span class="refTitle">"Guidelines for Writing an IANA Considerations Section in RFCs"</span>, <span class="seriesInfo">BCP 26</span>, <span class="seriesInfo">RFC 8126</span>, <span class="seriesInfo">DOI 10.17487/RFC8126</span>, <time datetime="2017-06">June 2017</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc8126">https://www.rfc-editor.org/info/rfc8126</a>&gt;</span>. </dd>
<dt id="RFC8174">[RFC8174]</dt>
<dd>
<span class="refAuthor">Leiba, B.</span>, <span class="refTitle">"Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words"</span>, <span class="seriesInfo">BCP 14</span>, <span class="seriesInfo">RFC 8174</span>, <span class="seriesInfo">DOI 10.17487/RFC8174</span>, <time datetime="2017-05">May 2017</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc8174">https://www.rfc-editor.org/info/rfc8174</a>&gt;</span>. </dd>
<dt id="RFC8231">[RFC8231]</dt>
<dd>
<span class="refAuthor">Crabbe, E.</span><span class="refAuthor">, Minei, I.</span><span class="refAuthor">, Medved, J.</span><span class="refAuthor">, and R. Varga</span>, <span class="refTitle">"Path Computation Element Communication Protocol (PCEP) Extensions for Stateful PCE"</span>, <span class="seriesInfo">RFC 8231</span>, <span class="seriesInfo">DOI 10.17487/RFC8231</span>, <time datetime="2017-09">September 2017</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc8231">https://www.rfc-editor.org/info/rfc8231</a>&gt;</span>. </dd>
<dt id="RFC8253">[RFC8253]</dt>
<dd>
<span class="refAuthor">Lopez, D.</span><span class="refAuthor">, Gonzalez de Dios, O.</span><span class="refAuthor">, Wu, Q.</span><span class="refAuthor">, and D. Dhody</span>, <span class="refTitle">"PCEPS: Usage of TLS to Provide a Secure Transport for the Path Computation Element Communication Protocol (PCEP)"</span>, <span class="seriesInfo">RFC 8253</span>, <span class="seriesInfo">DOI 10.17487/RFC8253</span>, <time datetime="2017-10">October 2017</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc8253">https://www.rfc-editor.org/info/rfc8253</a>&gt;</span>. </dd>
<dt id="RFC8281">[RFC8281]</dt>
<dd>
<span class="refAuthor">Crabbe, E.</span><span class="refAuthor">, Minei, I.</span><span class="refAuthor">, Sivabalan, S.</span><span class="refAuthor">, and R. Varga</span>, <span class="refTitle">"Path Computation Element Communication Protocol (PCEP) Extensions for PCE-Initiated LSP Setup in a Stateful PCE Model"</span>, <span class="seriesInfo">RFC 8281</span>, <span class="seriesInfo">DOI 10.17487/RFC8281</span>, <time datetime="2017-12">December 2017</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc8281">https://www.rfc-editor.org/info/rfc8281</a>&gt;</span>. </dd>
<dt id="RFC8697">[RFC8697]</dt>
<dd>
<span class="refAuthor">Minei, I.</span><span class="refAuthor">, Crabbe, E.</span><span class="refAuthor">, Sivabalan, S.</span><span class="refAuthor">, Ananthakrishnan, H.</span><span class="refAuthor">, Dhody, D.</span><span class="refAuthor">, and Y. Tanaka</span>, <span class="refTitle">"Path Computation Element Communication Protocol (PCEP) Extensions for Establishing Relationships between Sets of Label Switched Paths (LSPs)"</span>, <span class="seriesInfo">RFC 8697</span>, <span class="seriesInfo">DOI 10.17487/RFC8697</span>, <time datetime="2020-01">January 2020</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc8697">https://www.rfc-editor.org/info/rfc8697</a>&gt;</span>. </dd>
</dl>
</section>
<section id="section-9.2">
        <h3 id="name-informative-references">
<a href="#section-9.2" class="section-number selfRef">9.2. </a><a href="#name-informative-references" class="section-name selfRef">Informative References</a>
        </h3>
<dl class="references">
<dt id="I-D.ietf-pce-association-diversity">[PCEP-LSP-EXT]</dt>
<dd>
<span class="refAuthor">Litkowski, S.</span><span class="refAuthor">, Sivabalan, S.</span><span class="refAuthor">, Barth, C.</span><span class="refAuthor">, and M. Negi</span>, <span class="refTitle">"Path Computation Element Communication Protocol (PCEP) Extension for LSP Diversity Constraint Signaling"</span>, <span class="refContent">Work in Progress</span>, <span class="seriesInfo">Internet-Draft, draft-ietf-pce-association-diversity-14</span>, <time datetime="2020-01-26">26 January 2020</time>, <span>&lt;<a href="https://tools.ietf.org/html/draft-ietf-pce-association-diversity-14">https://tools.ietf.org/html/draft-ietf-pce-association-diversity-14</a>&gt;</span>. </dd>
<dt id="I-D.ietf-pce-pcep-yang">[PCEP-YANG]</dt>
<dd>
<span class="refAuthor">Dhody, D.</span><span class="refAuthor">, Hardwick, J.</span><span class="refAuthor">, Beeram, V.</span><span class="refAuthor">, and J. Tantsura</span>, <span class="refTitle">"A YANG Data Model for Path Computation Element Communications Protocol (PCEP)"</span>, <span class="refContent">Work in Progress</span>, <span class="seriesInfo">Internet-Draft, draft-ietf-pce-pcep-yang-13</span>, <time datetime="2019-10-31">31 October 2019</time>, <span>&lt;<a href="https://tools.ietf.org/html/draft-ietf-pce-pcep-yang-13">https://tools.ietf.org/html/draft-ietf-pce-pcep-yang-13</a>&gt;</span>. </dd>
<dt id="RFC4427">[RFC4427]</dt>
<dd>
<span class="refAuthor">Mannie, E., Ed.</span><span class="refAuthor"> and D. Papadimitriou, Ed.</span>, <span class="refTitle">"Recovery (Protection and Restoration) Terminology for Generalized Multi-Protocol Label Switching (GMPLS)"</span>, <span class="seriesInfo">RFC 4427</span>, <span class="seriesInfo">DOI 10.17487/RFC4427</span>, <time datetime="2006-03">March 2006</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc4427">https://www.rfc-editor.org/info/rfc4427</a>&gt;</span>. </dd>
<dt id="RFC4655">[RFC4655]</dt>
<dd>
<span class="refAuthor">Farrel, A.</span><span class="refAuthor">, Vasseur, J.-P.</span><span class="refAuthor">, and J. Ash</span>, <span class="refTitle">"A Path Computation Element (PCE)-Based Architecture"</span>, <span class="seriesInfo">RFC 4655</span>, <span class="seriesInfo">DOI 10.17487/RFC4655</span>, <time datetime="2006-08">August 2006</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc4655">https://www.rfc-editor.org/info/rfc4655</a>&gt;</span>. </dd>
<dt id="RFC4657">[RFC4657]</dt>
<dd>
<span class="refAuthor">Ash, J., Ed.</span><span class="refAuthor"> and J.L. Le Roux, Ed.</span>, <span class="refTitle">"Path Computation Element (PCE) Communication Protocol Generic Requirements"</span>, <span class="seriesInfo">RFC 4657</span>, <span class="seriesInfo">DOI 10.17487/RFC4657</span>, <time datetime="2006-09">September 2006</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc4657">https://www.rfc-editor.org/info/rfc4657</a>&gt;</span>. </dd>
<dt id="RFC7420">[RFC7420]</dt>
<dd>
<span class="refAuthor">Koushik, A.</span><span class="refAuthor">, Stephan, E.</span><span class="refAuthor">, Zhao, Q.</span><span class="refAuthor">, King, D.</span><span class="refAuthor">, and J. Hardwick</span>, <span class="refTitle">"Path Computation Element Communication Protocol (PCEP) Management Information Base (MIB) Module"</span>, <span class="seriesInfo">RFC 7420</span>, <span class="seriesInfo">DOI 10.17487/RFC7420</span>, <time datetime="2014-12">December 2014</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc7420">https://www.rfc-editor.org/info/rfc7420</a>&gt;</span>. </dd>
<dt id="RFC8051">[RFC8051]</dt>
<dd>
<span class="refAuthor">Zhang, X., Ed.</span><span class="refAuthor"> and I. Minei, Ed.</span>, <span class="refTitle">"Applicability of a Stateful Path Computation Element (PCE)"</span>, <span class="seriesInfo">RFC 8051</span>, <span class="seriesInfo">DOI 10.17487/RFC8051</span>, <time datetime="2017-01">January 2017</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc8051">https://www.rfc-editor.org/info/rfc8051</a>&gt;</span>. </dd>
<dt id="RFC8664">[RFC8664]</dt>
<dd>
<span class="refAuthor">Sivabalan, S.</span><span class="refAuthor">, Filsfils, C.</span><span class="refAuthor">, Tantsura, J.</span><span class="refAuthor">, Henderickx, W.</span><span class="refAuthor">, and J. Hardwick</span>, <span class="refTitle">"Path Computation Element Communication Protocol (PCEP) Extensions for Segment Routing"</span>, <span class="seriesInfo">RFC 8664</span>, <span class="seriesInfo">DOI 10.17487/RFC8664</span>, <time datetime="2019-12">December 2019</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc8664">https://www.rfc-editor.org/info/rfc8664</a>&gt;</span>. </dd>
<dt id="I-D.litkowski-pce-state-sync">[STATE-PCE-SYNC]</dt>
<dd>
<span class="refAuthor">Litkowski, S.</span><span class="refAuthor">, Sivabalan, S.</span><span class="refAuthor">, Li, C.</span><span class="refAuthor">, and H. Zheng</span>, <span class="refTitle">"Inter Stateful Path Computation Element (PCE) Communication Procedures."</span>, <span class="refContent">Work in Progress</span>, <span class="seriesInfo">Internet-Draft, draft-litkowski-pce-state-sync-07</span>, <time datetime="2020-01-11">11 January 2020</time>, <span>&lt;<a href="https://tools.ietf.org/html/draft-litkowski-pce-state-sync-07">https://tools.ietf.org/html/draft-litkowski-pce-state-sync-07</a>&gt;</span>. </dd>
</dl>
</section>
</section>
<section id="section-appendix.a">
      <h2 id="name-acknowledgments">
<a href="#name-acknowledgments" class="section-name selfRef">Acknowledgments</a>
      </h2>
<p id="section-appendix.a-1">We would like to thank  <span class="contact-name">Jeff Tantsura</span>,  <span class="contact-name">Xian Zhang</span>, and  <span class="contact-name">Greg Mirsky</span> for
      their contributions to this document.<a href="#section-appendix.a-1" class="pilcrow">¶</a></p>
<p id="section-appendix.a-2">Thanks to <span class="contact-name">Ines Robles</span> for the RTGDIR review.<a href="#section-appendix.a-2" class="pilcrow">¶</a></p>
<p id="section-appendix.a-3">Thanks to <span class="contact-name">Pete Resnick</span> for the GENART review.<a href="#section-appendix.a-3" class="pilcrow">¶</a></p>
<p id="section-appendix.a-4">Thanks to <span class="contact-name">Donald Eastlake</span> for the SECDIR review.<a href="#section-appendix.a-4" class="pilcrow">¶</a></p>
<p id="section-appendix.a-5">Thanks to  <span class="contact-name">Barry Leiba</span>,  <span class="contact-name">Benjamin Kaduk</span>,  <span class="contact-name">Éric Vyncke</span>, and  <span class="contact-name">Roman Danyliw</span> for the IESG review.<a href="#section-appendix.a-5" class="pilcrow">¶</a></p>
</section>
<section id="section-appendix.b">
      <h2 id="name-contributors">
<a href="#name-contributors" class="section-name selfRef">Contributors</a>
      </h2>
<address class="vcard">
        <div dir="auto" class="left"><span class="fn nameRole">Dhruv Dhody</span></div>
<div dir="auto" class="left"><span class="org">Huawei Technologies</span></div>
<div dir="auto" class="left"><span class="street-address">Divyashree Techno Park, Whitefield</span></div>
<div dir="auto" class="left">
<span class="locality">Bangalore</span> <span class="postal-code">560066</span>
</div>
<div dir="auto" class="left"><span class="region">Karnataka</span></div>
<div dir="auto" class="left"><span class="country-name">India</span></div>
<div class="email">
<span>Email:</span>
<a href="mailto:dhruv.ietf@gmail.com" class="email">dhruv.ietf@gmail.com</a>
</div>
</address>
<address class="vcard">
        <div dir="auto" class="left"><span class="fn nameRole">Raveendra Torvi</span></div>
<div dir="auto" class="left"><span class="org">Juniper Networks</span></div>
<div dir="auto" class="left"><span class="street-address">1194 N Mathilda Ave</span></div>
<div dir="auto" class="left">
<span class="locality">Sunnyvale</span>, <span class="region">CA</span> <span class="postal-code">94086</span>
</div>
<div dir="auto" class="left"><span class="country-name">United States of America</span></div>
<div class="email">
<span>Email:</span>
<a href="mailto:rtorvi@juniper.net" class="email">rtorvi@juniper.net</a>
</div>
</address>
<address class="vcard">
        <div dir="auto" class="left"><span class="fn nameRole">Edward Crabbe</span></div>
<div dir="auto" class="left"><span class="org">Individual Contributor</span></div>
<div class="email">
<span>Email:</span>
<a href="mailto:edward.crabbe@gmail.com" class="email">edward.crabbe@gmail.com</a>
</div>
</address>
</section>
<div id="authors-addresses">
<section id="section-appendix.c">
      <h2 id="name-authors-addresses">
<a href="#name-authors-addresses" class="section-name selfRef">Authors' Addresses</a>
      </h2>
<address class="vcard">
        <div dir="auto" class="left"><span class="fn nameRole">Hariharan Ananthakrishnan</span></div>
<div dir="auto" class="left"><span class="org">Netflix</span></div>
<div dir="auto" class="left"><span class="country-name">United States of America</span></div>
<div class="email">
<span>Email:</span>
<a href="mailto:hari@netflix.com" class="email">hari@netflix.com</a>
</div>
</address>
<address class="vcard">
        <div dir="auto" class="left"><span class="fn nameRole">Siva Sivabalan</span></div>
<div dir="auto" class="left"><span class="org">Cisco</span></div>
<div dir="auto" class="left"><span class="street-address">2000 Innovation Drive</span></div>
<div dir="auto" class="left">
<span class="locality">Kanata</span> <span class="region">Ontario</span> <span class="postal-code">K2K 3E8</span>
</div>
<div dir="auto" class="left"><span class="country-name">Canada</span></div>
<div class="email">
<span>Email:</span>
<a href="mailto:msiva@cisco.com" class="email">msiva@cisco.com</a>
</div>
</address>
<address class="vcard">
        <div dir="auto" class="left"><span class="fn nameRole">Colby Barth</span></div>
<div dir="auto" class="left"><span class="org">Juniper Networks</span></div>
<div dir="auto" class="left"><span class="street-address">1194 N Mathilda Ave</span></div>
<div dir="auto" class="left">
<span class="locality">Sunnyvale</span>, <span class="region">CA</span> <span class="postal-code">94086</span>
</div>
<div dir="auto" class="left"><span class="country-name">United States of America</span></div>
<div class="email">
<span>Email:</span>
<a href="mailto:cbarth@juniper.net" class="email">cbarth@juniper.net</a>
</div>
</address>
<address class="vcard">
        <div dir="auto" class="left"><span class="fn nameRole">Ina Minei</span></div>
<div dir="auto" class="left"><span class="org">Google, Inc</span></div>
<div dir="auto" class="left"><span class="street-address">1600 Amphitheatre Parkway</span></div>
<div dir="auto" class="left">
<span class="locality">Mountain View</span>, <span class="region">CA</span> <span class="postal-code">94043</span>
</div>
<div dir="auto" class="left"><span class="country-name">United States of America</span></div>
<div class="email">
<span>Email:</span>
<a href="mailto:inaminei@google.com" class="email">inaminei@google.com</a>
</div>
</address>
<address class="vcard">
        <div dir="auto" class="left"><span class="fn nameRole">Mahendra Singh Negi</span></div>
<div dir="auto" class="left"><span class="org">Huawei Technologies</span></div>
<div dir="auto" class="left"><span class="street-address">Divyashree Techno Park, Whitefield</span></div>
<div dir="auto" class="left">
<span class="locality">Bangalore</span> <span class="postal-code">560066</span>
</div>
<div dir="auto" class="left"><span class="region">Karnataka</span></div>
<div dir="auto" class="left"><span class="country-name">India</span></div>
<div class="email">
<span>Email:</span>
<a href="mailto:mahend.ietf@gmail.com" class="email">mahend.ietf@gmail.com</a>
</div>
</address>
</section>
</div>
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