File: rfc8850.html

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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 8850: Controlling Multiple Streams for Telepresence (CLUE) Protocol Data Channel</title>
<meta content="Christer Holmberg" name="author">
<meta content="
       
        This document defines how to use the WebRTC data channel
        mechanism to realize a data channel, referred to
        as a Controlling Multiple Streams for Telepresence (CLUE) data channel, for transporting CLUE protocol
        messages between two CLUE entities.
       
    " name="description">
<meta content="xml2rfc 3.5.0" name="generator">
<meta content="SIP" name="keyword">
<meta content="SDP" name="keyword">
<meta content="DTLS" name="keyword">
<meta content="SCTP" name="keyword">
<meta content="DATA" name="keyword">
<meta content="CHANNEL" name="keyword">
<meta content="DCEP" name="keyword">
<meta content="DATA_CHANNEL_OPEN" name="keyword">
<meta content="DATA_CHANNEL_ACK" name="keyword">
<meta content="PPID" name="keyword">
<meta content="TELEPRESENCE" name="keyword">
<meta content="RTCWEB" name="keyword">
<meta content="WEBRTC" name="keyword">
<meta content="8850" name="rfc.number">
<!-- Generator version information:
  xml2rfc 3.5.0
    Python 3.6.10
    appdirs 1.4.4
    ConfigArgParse 1.2.3
    google-i18n-address 2.3.5
    html5lib 1.0.1
    intervaltree 3.0.2
    Jinja2 2.11.2
    kitchen 1.2.6
    lxml 4.4.2
    pycairo 1.19.0
    pycountry 19.8.18
    pyflakes 2.1.1
    PyYAML 5.3.1
    requests 2.22.0
    setuptools 40.6.2
    six 1.14.0
    WeasyPrint 51
-->
<link href="rfc8850.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;
  }

}
/* 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;
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<link href="https://dx.doi.org/10.17487/rfc8850" rel="alternate">
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<table class="ears">
<thead><tr>
<td class="left">RFC 8850</td>
<td class="center">CLUE Data Channel</td>
<td class="right">January 2021</td>
</tr></thead>
<tfoot><tr>
<td class="left">Holmberg</td>
<td class="center">Experimental</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/rfc8850" class="eref">8850</a></dd>
<dt class="label-category">Category:</dt>
<dd class="category">Experimental</dd>
<dt class="label-published">Published:</dt>
<dd class="published">
<time datetime="2021-01" class="published">January 2021</time>
    </dd>
<dt class="label-issn">ISSN:</dt>
<dd class="issn">2070-1721</dd>
<dt class="label-authors">Author:</dt>
<dd class="authors">
<div class="author">
      <div class="author-name">C. Holmberg</div>
<div class="org">Ericsson</div>
</div>
</dd>
</dl>
</div>
<h1 id="rfcnum">RFC 8850</h1>
<h1 id="title">Controlling Multiple Streams for Telepresence (CLUE) Protocol Data Channel</h1>
<section id="section-abstract">
      <h2 id="abstract"><a href="#abstract" class="selfRef">Abstract</a></h2>
<p id="section-abstract-1">
        This document defines how to use the WebRTC data channel
        mechanism to realize a data channel, referred to
        as a Controlling Multiple Streams for Telepresence (CLUE) data channel, for transporting CLUE protocol
        messages between two CLUE entities.<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 document is not an Internet Standards Track specification; it is
            published for examination, experimental implementation, and
            evaluation.<a href="#section-boilerplate.1-1" class="pilcrow">¶</a></p>
<p id="section-boilerplate.1-2">
            This document defines an Experimental Protocol for the Internet
            community.  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).  Not all documents
            approved by the IESG are candidates for any level of Internet
            Standard; see 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/rfc8850">https://www.rfc-editor.org/info/rfc8850</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>
        </h2>
<p id="section-boilerplate.2-1">
            Copyright (c) 2021 IETF Trust and the persons identified as the
            document authors. All rights reserved.<a href="#section-boilerplate.2-1" class="pilcrow">¶</a></p>
<p id="section-boilerplate.2-2">
            This document is subject to BCP 78 and the IETF Trust's Legal
            Provisions Relating to IETF Documents
            (<span><a href="https://trustee.ietf.org/license-info">https://trustee.ietf.org/license-info</a></span>) in effect on the date of
            publication of this document. Please review these documents
            carefully, as they describe your rights and restrictions with
            respect to this document. Code Components extracted from this
            document must include 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="compact toc ulEmpty">
<li class="compact toc ulEmpty" id="section-toc.1-1.1">
            <p id="section-toc.1-1.1.1" class="keepWithNext"><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>
</li>
          <li class="compact toc ulEmpty" id="section-toc.1-1.2">
            <p id="section-toc.1-1.2.1" class="keepWithNext"><a href="#section-2" class="xref">2</a>.  <a href="#name-conventions" class="xref">Conventions</a><a href="#section-toc.1-1.2.1" class="pilcrow">¶</a></p>
</li>
          <li class="compact 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-clue-data-channel" class="xref">CLUE Data Channel</a><a href="#section-toc.1-1.3.1" class="pilcrow">¶</a></p>
<ul class="compact toc ulEmpty">
<li class="compact toc ulEmpty" id="section-toc.1-1.3.2.1">
                <p id="section-toc.1-1.3.2.1.1" class="keepWithNext"><a href="#section-3.1" class="xref">3.1</a>.  <a href="#name-general" class="xref">General</a><a href="#section-toc.1-1.3.2.1.1" class="pilcrow">¶</a></p>
</li>
              <li class="compact 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-sctp-considerations" class="xref">SCTP Considerations</a><a href="#section-toc.1-1.3.2.2.1" class="pilcrow">¶</a></p>
<ul class="compact toc ulEmpty">
<li class="compact toc ulEmpty" id="section-toc.1-1.3.2.2.2.1">
                    <p id="section-toc.1-1.3.2.2.2.1.1"><a href="#section-3.2.1" class="xref">3.2.1</a>.  <a href="#name-general-2" class="xref">General</a><a href="#section-toc.1-1.3.2.2.2.1.1" class="pilcrow">¶</a></p>
</li>
                  <li class="compact toc ulEmpty" id="section-toc.1-1.3.2.2.2.2">
                    <p id="section-toc.1-1.3.2.2.2.2.1"><a href="#section-3.2.2" class="xref">3.2.2</a>.  <a href="#name-sctp-payload-protocol-ident" class="xref">SCTP Payload Protocol Identifier (PPID)</a><a href="#section-toc.1-1.3.2.2.2.2.1" class="pilcrow">¶</a></p>
</li>
                  <li class="compact toc ulEmpty" id="section-toc.1-1.3.2.2.2.3">
                    <p id="section-toc.1-1.3.2.2.2.3.1"><a href="#section-3.2.3" class="xref">3.2.3</a>.  <a href="#name-reliability" class="xref">Reliability</a><a href="#section-toc.1-1.3.2.2.2.3.1" class="pilcrow">¶</a></p>
</li>
                  <li class="compact toc ulEmpty" id="section-toc.1-1.3.2.2.2.4">
                    <p id="section-toc.1-1.3.2.2.2.4.1"><a href="#section-3.2.4" class="xref">3.2.4</a>.  <a href="#name-order" class="xref">Order</a><a href="#section-toc.1-1.3.2.2.2.4.1" class="pilcrow">¶</a></p>
</li>
                  <li class="compact toc ulEmpty" id="section-toc.1-1.3.2.2.2.5">
                    <p id="section-toc.1-1.3.2.2.2.5.1"><a href="#section-3.2.5" class="xref">3.2.5</a>.  <a href="#name-stream-reset" class="xref">Stream Reset</a><a href="#section-toc.1-1.3.2.2.2.5.1" class="pilcrow">¶</a></p>
</li>
                  <li class="compact toc ulEmpty" id="section-toc.1-1.3.2.2.2.6">
                    <p id="section-toc.1-1.3.2.2.2.6.1"><a href="#section-3.2.6" class="xref">3.2.6</a>.  <a href="#name-sctp-multihoming" class="xref">SCTP Multihoming</a><a href="#section-toc.1-1.3.2.2.2.6.1" class="pilcrow">¶</a></p>
</li>
                  <li class="compact toc ulEmpty" id="section-toc.1-1.3.2.2.2.7">
                    <p id="section-toc.1-1.3.2.2.2.7.1"><a href="#section-3.2.7" class="xref">3.2.7</a>.  <a href="#name-closing-the-clue-data-chann" class="xref">Closing the CLUE Data Channel</a><a href="#section-toc.1-1.3.2.2.2.7.1" class="pilcrow">¶</a></p>
</li>
                </ul>
</li>
              <li class="compact toc ulEmpty" id="section-toc.1-1.3.2.3">
                <p id="section-toc.1-1.3.2.3.1"><a href="#section-3.3" class="xref">3.3</a>.  <a href="#name-sdp-considerations" class="xref">SDP Considerations</a><a href="#section-toc.1-1.3.2.3.1" class="pilcrow">¶</a></p>
<ul class="compact toc ulEmpty">
<li class="compact toc ulEmpty" id="section-toc.1-1.3.2.3.2.1">
                    <p id="section-toc.1-1.3.2.3.2.1.1"><a href="#section-3.3.1" class="xref">3.3.1</a>.  <a href="#name-general-3" class="xref">General</a><a href="#section-toc.1-1.3.2.3.2.1.1" class="pilcrow">¶</a></p>
</li>
                  <li class="compact toc ulEmpty" id="section-toc.1-1.3.2.3.2.2">
                    <p id="section-toc.1-1.3.2.3.2.2.1"><a href="#section-3.3.2" class="xref">3.3.2</a>.  <a href="#name-sdp-dcmap-attribute" class="xref">SDP dcmap Attribute</a><a href="#section-toc.1-1.3.2.3.2.2.1" class="pilcrow">¶</a></p>
</li>
                  <li class="compact toc ulEmpty" id="section-toc.1-1.3.2.3.2.3">
                    <p id="section-toc.1-1.3.2.3.2.3.1"><a href="#section-3.3.3" class="xref">3.3.3</a>.  <a href="#name-sdp-dcsa-attribute" class="xref">SDP dcsa Attribute</a><a href="#section-toc.1-1.3.2.3.2.3.1" class="pilcrow">¶</a></p>
</li>
                  <li class="compact toc ulEmpty" id="section-toc.1-1.3.2.3.2.4">
                    <p id="section-toc.1-1.3.2.3.2.4.1"><a href="#section-3.3.4" class="xref">3.3.4</a>.  <a href="#name-example" class="xref">Example</a><a href="#section-toc.1-1.3.2.3.2.4.1" class="pilcrow">¶</a></p>
</li>
                </ul>
</li>
            </ul>
</li>
          <li class="compact 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-security-considerations" class="xref">Security Considerations</a><a href="#section-toc.1-1.4.1" class="pilcrow">¶</a></p>
</li>
          <li class="compact 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-iana-considerations" class="xref">IANA Considerations</a><a href="#section-toc.1-1.5.1" class="pilcrow">¶</a></p>
<ul class="compact toc ulEmpty">
<li class="compact toc ulEmpty" id="section-toc.1-1.5.2.1">
                <p id="section-toc.1-1.5.2.1.1"><a href="#section-5.1" class="xref">5.1</a>.  <a href="#name-subprotocol-identifier-clue" class="xref">Subprotocol Identifier "clue"</a><a href="#section-toc.1-1.5.2.1.1" class="pilcrow">¶</a></p>
</li>
            </ul>
</li>
          <li class="compact 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-references" class="xref">References</a><a href="#section-toc.1-1.6.1" class="pilcrow">¶</a></p>
<ul class="compact toc ulEmpty">
<li class="compact 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-normative-references" class="xref">Normative References</a><a href="#section-toc.1-1.6.2.1.1" class="pilcrow">¶</a></p>
</li>
              <li class="compact 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-informative-references" class="xref">Informative References</a><a href="#section-toc.1-1.6.2.2.1" class="pilcrow">¶</a></p>
</li>
            </ul>
</li>
          <li class="compact toc ulEmpty" id="section-toc.1-1.7">
            <p id="section-toc.1-1.7.1"><a href="#section-appendix.a" class="xref"></a><a href="#name-acknowledgements" class="xref">Acknowledgements</a><a href="#section-toc.1-1.7.1" class="pilcrow">¶</a></p>
</li>
          <li class="compact toc ulEmpty" id="section-toc.1-1.8">
            <p id="section-toc.1-1.8.1"><a href="#section-appendix.b" class="xref"></a><a href="#name-authors-address" class="xref">Author's Address</a><a href="#section-toc.1-1.8.1" class="pilcrow">¶</a></p>
</li>
        </ul>
</nav>
</section>
</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">
        This document defines how to use the WebRTC data channel
        mechanism <span>[<a href="#RFC8831" class="xref">RFC8831</a>]</span> to realize a
        data channel, referred to as a Controlling Multiple Streams for
 Telepresence (CLUE) data channel, for
        transporting CLUE protocol messages <span>[<a href="#RFC8847" class="xref">RFC8847</a>]</span> between two CLUE entities.<a href="#section-1-1" class="pilcrow">¶</a></p>
<p id="section-1-2">
        This document also defines how to describe the SCTPoDTLS association
        <span>[<a href="#RFC8261" class="xref">RFC8261</a>]</span> (also referred to as
        "SCTP over DTLS" in this document) used to 
                realize the CLUE data channel using the Session Description Protocol (SDP) 
                <span>[<a href="#RFC4566" class="xref">RFC4566</a>]</span> and defines usage of the
        SDP-based "SCTP over DTLS" data channel negotiation mechanism
        <span>[<a href="#RFC8864" class="xref">RFC8864</a>]</span>. ("SCTP" stands for "Stream
 Control Transmission Protocol".) This includes SCTP
        considerations specific to a CLUE data channel, the SDP media
        description ("m=" line) values, and usage of SDP attributes specific
        to a CLUE data channel.<a href="#section-1-2" class="pilcrow">¶</a></p>
<p id="section-1-3">
        Details and procedures associated with the CLUE protocol, and the
        SDP Offer/Answer procedures <span>[<a href="#RFC3264" class="xref">RFC3264</a>]</span>
        for negotiating usage of a CLUE data channel, are outside
        the scope of this document.<a href="#section-1-3" class="pilcrow">¶</a></p>
<aside id="section-1-4">
        <p id="section-1-4.1">NOTE: The usage of the Data Channel Establishment Protocol (DCEP)
        <span>[<a href="#RFC8832" class="xref">RFC8832</a>]</span>
        for establishing a CLUE data channel is outside the scope of this document.<a href="#section-1-4.1" class="pilcrow">¶</a></p>
</aside>
</section>
<section id="section-2">
      <h2 id="name-conventions">
<a href="#section-2" class="section-number selfRef">2. </a><a href="#name-conventions" class="section-name selfRef">Conventions</a>
      </h2>
<p id="section-2-1">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-2-1" class="pilcrow">¶</a></p>
<span class="break"></span><dl class="dlNewline" id="section-2-2">
        <dt id="section-2-2.1">SCTPoDTLS association</dt>
        <dd style="margin-left: 1.5em" id="section-2-2.2">Refers to an SCTP association carried over a DTLS connection <span>[<a href="#RFC8261" class="xref">RFC8261</a>]</span>.<a href="#section-2-2.2" class="pilcrow">¶</a>
</dd>
        <dd class="break"></dd>
<dt id="section-2-2.3">WebRTC data channel</dt>
        <dd style="margin-left: 1.5em" id="section-2-2.4">Refers to a pair of SCTP streams over an
SCTPoDTLS association that is used to transport non-media
data between two entities, as defined in <span>[<a href="#RFC8831" class="xref">RFC8831</a>]</span>.<a href="#section-2-2.4" class="pilcrow">¶</a>
</dd>
        <dd class="break"></dd>
<dt id="section-2-2.5">CLUE data channel</dt>
        <dd style="margin-left: 1.5em" id="section-2-2.6">Refers to a WebRTC data channel realization <span>[<a href="#RFC8831" class="xref">RFC8831</a>]</span>, with a specific set of
SCTP characteristics, with the purpose of transporting CLUE
protocol messages <span>[<a href="#RFC8847" class="xref">RFC8847</a>]</span> between two CLUE entities.<a href="#section-2-2.6" class="pilcrow">¶</a>
</dd>
        <dd class="break"></dd>
<dt id="section-2-2.7">CLUE entity</dt>
        <dd style="margin-left: 1.5em" id="section-2-2.8">Refers to a SIP User Agent (UA) <span>[<a href="#RFC3261" class="xref">RFC3261</a>]</span> that supports the CLUE data channel
and the CLUE protocol.<a href="#section-2-2.8" class="pilcrow">¶</a>
</dd>
        <dd class="break"></dd>
<dt id="section-2-2.9">CLUE session</dt>
        <dd style="margin-left: 1.5em" id="section-2-2.10">Refers to a SIP session <span>[<a href="#RFC3261" class="xref">RFC3261</a>]</span> between two SIP UAs, where a
CLUE data channel, associated with the SIP session, has been
established between the SIP UAs.<a href="#section-2-2.10" class="pilcrow">¶</a>
</dd>
        <dd class="break"></dd>
<dt id="section-2-2.11">SCTP stream</dt>
        <dd style="margin-left: 1.5em" id="section-2-2.12">Defined in <span>[<a href="#RFC4960" class="xref">RFC4960</a>]</span> as a unidirectional logical channel
established from one to another associated SCTP endpoint,
within which all user messages are delivered in sequence except
for those submitted to the unordered delivery service.<a href="#section-2-2.12" class="pilcrow">¶</a>
</dd>
        <dd class="break"></dd>
<dt id="section-2-2.13">SCTP stream identifier</dt>
        <dd style="margin-left: 1.5em" id="section-2-2.14">Defined in <span>[<a href="#RFC4960" class="xref">RFC4960</a>]</span> as an unsigned
    integer.  Identifies an SCTP stream.<a href="#section-2-2.14" class="pilcrow">¶</a>
</dd>
      <dd class="break"></dd>
</dl>
</section>
<div id="section.dtls">
<section id="section-3">
      <h2 id="name-clue-data-channel">
<a href="#section-3" class="section-number selfRef">3. </a><a href="#name-clue-data-channel" class="section-name selfRef">CLUE Data Channel</a>
      </h2>
<div id="section.cdc.gen">
<section id="section-3.1">
        <h3 id="name-general">
<a href="#section-3.1" class="section-number selfRef">3.1. </a><a href="#name-general" class="section-name selfRef">General</a>
        </h3>
<p id="section-3.1-1">
        This section describes the realization of a CLUE data channel,
        using the WebRTC data channel mechanism.
        This includes a set of SCTP characteristics specific to a
        CLUE data channel, the values of the "m=" line describing
        the SCTPoDTLS association associated with the WebRTC
        data channel, and the usage of the SDP-based "SCTP
        over DTLS" data channel negotiation mechanism for creating the
        CLUE data channel.<a href="#section-3.1-1" class="pilcrow">¶</a></p>
<p id="section-3.1-2">
        As described in <span>[<a href="#RFC8831" class="xref">RFC8831</a>]</span>, the SCTP streams realizing
        a WebRTC data channel must be associated with the same SCTP association.
        In addition, both SCTP streams realizing the WebRTC data channel must
        use the same SCTP stream identifier value. These rules also apply to
        a CLUE data channel.<a href="#section-3.1-2" class="pilcrow">¶</a></p>
<p id="section-3.1-3">
        Within a given CLUE session, a CLUE entity <span class="bcp14">MUST</span> use a single CLUE
        data channel for transport of all CLUE messages towards its peer.<a href="#section-3.1-3" class="pilcrow">¶</a></p>
</section>
</div>
<div id="section.cdc.sctp">
<section id="section-3.2">
        <h3 id="name-sctp-considerations">
<a href="#section-3.2" class="section-number selfRef">3.2. </a><a href="#name-sctp-considerations" class="section-name selfRef">SCTP Considerations</a>
        </h3>
<div id="section.cdc.sctp.gen">
<section id="section-3.2.1">
          <h4 id="name-general-2">
<a href="#section-3.2.1" class="section-number selfRef">3.2.1. </a><a href="#name-general-2" class="section-name selfRef">General</a>
          </h4>
<p id="section-3.2.1-1">
                As described in <span>[<a href="#RFC8831" class="xref">RFC8831</a>]</span>, different SCTP options
                (e.g., regarding ordered delivery) can be used for a
                data channel. This section describes the SCTP options
                used for a CLUE data channel. <a href="#section.oa" class="xref">Section 3.3</a> describes how SCTP options are signaled using SDP.<a href="#section-3.2.1-1" class="pilcrow">¶</a></p>
</section>
</div>
<div id="section.cdc.sctp.ppid">
<section id="section-3.2.2">
          <h4 id="name-sctp-payload-protocol-ident">
<a href="#section-3.2.2" class="section-number selfRef">3.2.2. </a><a href="#name-sctp-payload-protocol-ident" class="section-name selfRef">SCTP Payload Protocol Identifier (PPID)</a>
          </h4>
<p id="section-3.2.2-1">
                A CLUE entity <span class="bcp14">MUST</span> use the PPID value 51 when sending a CLUE message
                on a CLUE data channel.<a href="#section-3.2.2-1" class="pilcrow">¶</a></p>
<aside id="section-3.2.2-2">
            <p id="section-3.2.2-2.1">
                   NOTE: As described in <span>[<a href="#RFC8831" class="xref">RFC8831</a>]</span>, the PPID value 51 indicates that
                the SCTP message contains data encoded in UTF-8 format. The PPID
                value 51 does not indicate which application protocol the SCTP message
                is associated with -- only the format in which the data is encoded.<a href="#section-3.2.2-2.1" class="pilcrow">¶</a></p>
</aside>
</section>
</div>
<div id="section.cdc.sctp.reliability">
<section id="section-3.2.3">
          <h4 id="name-reliability">
<a href="#section-3.2.3" class="section-number selfRef">3.2.3. </a><a href="#name-reliability" class="section-name selfRef">Reliability</a>
          </h4>
<p id="section-3.2.3-1">
                The usage of SCTP for the CLUE data channel ensures reliable transport of 
                CLUE protocol messages <span>[<a href="#RFC8847" class="xref">RFC8847</a>]</span>.<a href="#section-3.2.3-1" class="pilcrow">¶</a></p>
<p id="section-3.2.3-2">
                <span>[<a href="#RFC8831" class="xref">RFC8831</a>]</span>
            requires the support of the partial reliability extension defined in <span>[<a href="#RFC3758" class="xref">RFC3758</a>]</span> and the limited retransmission policy defined in
            <span>[<a href="#RFC7496" class="xref">RFC7496</a>]</span>. A CLUE entity <span class="bcp14">MUST NOT</span> use 
                these extensions, as messages are required to always be sent reliably. A CLUE entity <span class="bcp14">MUST</span> 
                terminate the session if it detects that the peer entity uses any of the extensions.<a href="#section-3.2.3-2" class="pilcrow">¶</a></p>
</section>
</div>
<div id="section.cdc.sctp.order">
<section id="section-3.2.4">
          <h4 id="name-order">
<a href="#section-3.2.4" class="section-number selfRef">3.2.4. </a><a href="#name-order" class="section-name selfRef">Order</a>
          </h4>
<p id="section-3.2.4-1">
                A CLUE entity <span class="bcp14">MUST</span> use the ordered delivery SCTP service, as
                described in <span>[<a href="#RFC4960" class="xref">RFC4960</a>]</span>,
                for the CLUE data channel.<a href="#section-3.2.4-1" class="pilcrow">¶</a></p>
</section>
</div>
<div id="section.cdc.sctp.streamreset">
<section id="section-3.2.5">
          <h4 id="name-stream-reset">
<a href="#section-3.2.5" class="section-number selfRef">3.2.5. </a><a href="#name-stream-reset" class="section-name selfRef">Stream Reset</a>
          </h4>
<p id="section-3.2.5-1">
                A CLUE entity <span class="bcp14">MUST</span> support the stream reset extension defined in <span>[<a href="#RFC6525" class="xref">RFC6525</a>]</span>.<a href="#section-3.2.5-1" class="pilcrow">¶</a></p>
<p id="section-3.2.5-2">
                Per <span>[<a href="#RFC8831" class="xref">RFC8831</a>]</span>,
                the dynamic address reconfiguration extension parameter ('Supported Extensions Parameter')
                defined in <span>[<a href="#RFC5061" class="xref">RFC5061</a>]</span> must be used to signal the
            support of the stream reset extension defined in <span>[<a href="#RFC6525" class="xref">RFC6525</a>]</span>.
 Other features defined in <span>[<a href="#RFC5061" class="xref">RFC5061</a>]</span>
            <span class="bcp14">MUST NOT</span> be used for CLUE data channels.<a href="#section-3.2.5-2" class="pilcrow">¶</a></p>
</section>
</div>
<div id="section.cdc.sctp.multihome">
<section id="section-3.2.6">
          <h4 id="name-sctp-multihoming">
<a href="#section-3.2.6" class="section-number selfRef">3.2.6. </a><a href="#name-sctp-multihoming" class="section-name selfRef">SCTP Multihoming</a>
          </h4>
<p id="section-3.2.6-1">
                SCTP multihoming is not supported for SCTPoDTLS associations
 and therefore cannot be used for a CLUE data channel.<a href="#section-3.2.6-1" class="pilcrow">¶</a></p>
</section>
</div>
<div id="section.cdcp.proc.close">
<section id="section-3.2.7">
          <h4 id="name-closing-the-clue-data-chann">
<a href="#section-3.2.7" class="section-number selfRef">3.2.7. </a><a href="#name-closing-the-clue-data-chann" class="section-name selfRef">Closing the CLUE Data Channel</a>
          </h4>
<p id="section-3.2.7-1">
                As described in <span>[<a href="#RFC8831" class="xref">RFC8831</a>]</span>, to close a data channel, an entity sends an SCTP reset
                message <span>[<a href="#RFC6525" class="xref">RFC6525</a>]</span> on its outgoing
                SCTP stream associated with the data channel. When the remote peer receives the reset
                message, it also sends (unless already sent) a reset message on its outgoing SCTP
                stream associated with the data channel. The SCTPoDTLS association, and other data channels
                established on the same association, are not affected by the SCTP reset messages.<a href="#section-3.2.7-1" class="pilcrow">¶</a></p>
</section>
</div>
</section>
</div>
<div id="section.oa">
<section id="section-3.3">
        <h3 id="name-sdp-considerations">
<a href="#section-3.3" class="section-number selfRef">3.3. </a><a href="#name-sdp-considerations" class="section-name selfRef">SDP Considerations</a>
        </h3>
<div id="section.oa.gen">
<section id="section-3.3.1">
          <h4 id="name-general-3">
<a href="#section-3.3.1" class="section-number selfRef">3.3.1. </a><a href="#name-general-3" class="section-name selfRef">General</a>
          </h4>
<p id="section-3.3.1-1">This section defines how to (1) construct the SDP media description
          ("m=" line) for describing the SCTPoDTLS association used to realize
          a CLUE data channel and (2) use the
          SDP-based "SCTP over DTLS" data  channel negotiation mechanism
          <span>[<a href="#RFC8864" class="xref">RFC8864</a>]</span> for establishing
          a CLUE data channel on the SCTPoDTLS association.<a href="#section-3.3.1-1" class="pilcrow">¶</a></p>
<aside id="section-3.3.1-2">
            <p id="section-3.3.1-2.1">
                NOTE: Protocols other than SDP for negotiating usage of an SCTPoDTLS
                association for realizing a CLUE data channel are outside the scope
                of this specification.<a href="#section-3.3.1-2.1" class="pilcrow">¶</a></p>
</aside>
<p id="section-3.3.1-3">
                <span>[<a href="#RFC8848" class="xref">RFC8848</a>]</span>
                describes the SDP Offer/Answer procedures for negotiating a CLUE session,
                including the CLUE-controlled media streams and the CLUE data channel.<a href="#section-3.3.1-3" class="pilcrow">¶</a></p>
<div id="section.oa.mediadesc">
<section id="section-3.3.1.1">
            <h5 id="name-sdp-media-description-field">
<a href="#section-3.3.1.1" class="section-number selfRef">3.3.1.1. </a><a href="#name-sdp-media-description-field" class="section-name selfRef">SDP Media Description Fields</a>
            </h5>
<p id="section-3.3.1.1-1">
                    <span>[<a href="#RFC8841" class="xref">RFC8841</a>]</span> defines how
                to set the values of an "m=" line describing an SCTPoDTLS association. As defined in
                <span>[<a href="#RFC8841" class="xref">RFC8841</a>]</span>, for a 
                CLUE data channel the values are set as follows:<a href="#section-3.3.1.1-1" class="pilcrow">¶</a></p>
<span id="name-sdp-proto-field-values"></span><div id="table_SDP_mediadesc">
<table class="center" id="table-1">
              <caption>
<a href="#table-1" class="selfRef">Table 1</a>:
<a href="#name-sdp-proto-field-values" class="selfRef">SDP "proto" Field Values</a>
              </caption>
<thead>
                <tr>
                  <th class="text-center" rowspan="1" colspan="1">media</th>
                  <th class="text-center" rowspan="1" colspan="1">port</th>
                  <th class="text-center" rowspan="1" colspan="1">proto</th>
                  <th class="text-center" rowspan="1" colspan="1">fmt</th>
                </tr>
              </thead>
              <tbody>
                <tr>
                  <td class="text-center" rowspan="1" colspan="1">"application"</td>
                  <td class="text-center" rowspan="1" colspan="1">UDP port value</td>
                  <td class="text-center" rowspan="1" colspan="1">"UDP/DTLS/SCTP"</td>
                  <td class="text-center" rowspan="1" colspan="1">"webrtc-datachannel"</td>
                </tr>
                <tr>
                  <td class="text-center" rowspan="1" colspan="1">"application"</td>
                  <td class="text-center" rowspan="1" colspan="1">TCP port value</td>
                  <td class="text-center" rowspan="1" colspan="1">"TCP/DTLS/SCTP"</td>
                  <td class="text-center" rowspan="1" colspan="1">"webrtc-datachannel"</td>
                </tr>
              </tbody>
            </table>
</div>
<p id="section-3.3.1.1-3">
                CLUE entities <span class="bcp14">SHOULD NOT</span> transport the SCTPoDTLS association used to
                realize the CLUE data channel over TCP (using the "TCP/DTLS/SCTP"
                proto value), unless it is known that UDP/DTLS/SCTP will not work
                (for instance, when the Interactive Connectivity Establishment
                (ICE) mechanism <span>[<a href="#RFC8445" class="xref">RFC8445</a>]</span>
                is used and the ICE procedures determine that TCP transport is required).<a href="#section-3.3.1.1-3" class="pilcrow">¶</a></p>
</section>
</div>
<div id="section.oa.sctpport">
<section id="section-3.3.1.2">
            <h5 id="name-sdp-sctp-port-attribute">
<a href="#section-3.3.1.2" class="section-number selfRef">3.3.1.2. </a><a href="#name-sdp-sctp-port-attribute" class="section-name selfRef">SDP sctp-port Attribute</a>
            </h5>
<p id="section-3.3.1.2-1">
                As defined in <span>[<a href="#RFC8841" class="xref">RFC8841</a>]</span>,
                the SDP sctp-port attribute value is set to the SCTP port of the SCTPoDTLS association. A
                CLUE entity can choose any valid SCTP port value <span>[<a href="#RFC8841" class="xref">RFC8841</a>]</span>.<a href="#section-3.3.1.2-1" class="pilcrow">¶</a></p>
</section>
</div>
</section>
</div>
<div id="section.oa.dcmap">
<section id="section-3.3.2">
          <h4 id="name-sdp-dcmap-attribute">
<a href="#section-3.3.2" class="section-number selfRef">3.3.2. </a><a href="#name-sdp-dcmap-attribute" class="section-name selfRef">SDP dcmap Attribute</a>
          </h4>
<p id="section-3.3.2-1">
                The values of the SDP dcmap attribute <span>[<a href="#RFC8864" class="xref">RFC8864</a>]</span>, associated with the "m=" line describing the SCTPoDTLS
                association used to realize the WebRTC data channel, are set as follows:<a href="#section-3.3.2-1" class="pilcrow">¶</a></p>
<span id="name-sdp-dcmap-attribute-values"></span><div id="table_SDP_dcmap">
<table class="center" id="table-2">
            <caption>
<a href="#table-2" class="selfRef">Table 2</a>:
<a href="#name-sdp-dcmap-attribute-values" class="selfRef">SDP dcmap Attribute Values</a>
            </caption>
<thead>
              <tr>
                <th class="text-center" rowspan="1" colspan="1">stream-id</th>
                <th class="text-center" rowspan="1" colspan="1">subprotocol</th>
                <th class="text-center" rowspan="1" colspan="1">label</th>
                <th class="text-center" rowspan="1" colspan="1">ordered</th>
                <th class="text-center" rowspan="1" colspan="1">max-retr</th>
                <th class="text-center" rowspan="1" colspan="1">max-time</th>
              </tr>
            </thead>
            <tbody>
              <tr>
                <td class="text-center" rowspan="1" colspan="1">Value of the SCTP stream used to realize the CLUE data channel</td>
                <td class="text-center" rowspan="1" colspan="1">"CLUE"</td>
                <td class="text-center" rowspan="1" colspan="1">Application specific</td>
                <td class="text-center" rowspan="1" colspan="1">"true"</td>
                <td class="text-center" rowspan="1" colspan="1">N/A</td>
                <td class="text-center" rowspan="1" colspan="1">N/A</td>
              </tr>
            </tbody>
          </table>
</div>
<aside id="section-3.3.2-3">
            <p id="section-3.3.2-3.1">
                NOTE: As CLUE entities are required to use ordered SCTP message delivery,
                with full reliability, according to the procedures in
                <span>[<a href="#RFC8864" class="xref">RFC8864</a>]</span> the max-retr and max-time attribute parameters
                are not used when negotiating CLUE data channels.<a href="#section-3.3.2-3.1" class="pilcrow">¶</a></p>
</aside>
</section>
</div>
<div id="section.oa.dcsa">
<section id="section-3.3.3">
          <h4 id="name-sdp-dcsa-attribute">
<a href="#section-3.3.3" class="section-number selfRef">3.3.3. </a><a href="#name-sdp-dcsa-attribute" class="section-name selfRef">SDP dcsa Attribute</a>
          </h4>
<p id="section-3.3.3-1">
                The SDP dcsa attribute <span>[<a href="#RFC8864" class="xref">RFC8864</a>]</span> is not used when establishing a CLUE data channel.<a href="#section-3.3.3-1" class="pilcrow">¶</a></p>
</section>
</div>
<div id="section.oa.example">
<section id="section-3.3.4">
          <h4 id="name-example">
<a href="#section-3.3.4" class="section-number selfRef">3.3.4. </a><a href="#name-example" class="section-name selfRef">Example</a>
          </h4>
<p id="section-3.3.4-1">
                The example in <a href="#figure_SDP_example" class="xref">Figure 1</a> shows 
                an SDP media description for a CLUE data channel. Complete SDP examples can be found 
                in <span>[<a href="#RFC8848" class="xref">RFC8848</a>]</span>.<a href="#section-3.3.4-1" class="pilcrow">¶</a></p>
<span id="name-sdp-media-description-for-a"></span><div id="figure_SDP_example">
<figure id="figure-1">
            <div id="section-3.3.4-2.1">
<pre class="sourcecode lang-sdp">
         m=application 54111 UDP/DTLS/SCTP webrtc-datachannel
         a=sctp-port: 5000
         a=dcmap:2 subprotocol="CLUE";ordered=true</pre>
</div>
<figcaption><a href="#figure-1" class="selfRef">Figure 1</a>:
<a href="#name-sdp-media-description-for-a" class="selfRef">SDP Media Description for a CLUE Data Channel</a>
            </figcaption></figure>
</div>
</section>
</div>
</section>
</div>
</section>
</div>
<div id="section.sec">
<section id="section-4">
      <h2 id="name-security-considerations">
<a href="#section-4" class="section-number selfRef">4. </a><a href="#name-security-considerations" class="section-name selfRef">Security Considerations</a>
      </h2>
<p id="section-4-1">
                This specification relies on the security properties of the WebRTC data channel described in
                <span>[<a href="#RFC8831" class="xref">RFC8831</a>]</span>, including
                reliance on DTLS. Since CLUE sessions are established using SIP/SDP, protecting the data
                channel against message modification and recovery requires the use of SIP authentication
                and authorization mechanisms described in <span>[<a href="#RFC3261" class="xref">RFC3261</a>]</span>
                for session establishment prior to establishing the data channel.<a href="#section-4-1" class="pilcrow">¶</a></p>
</section>
</div>
<div id="section.iana">
<section id="section-5">
      <h2 id="name-iana-considerations">
<a href="#section-5" class="section-number selfRef">5. </a><a href="#name-iana-considerations" class="section-name selfRef">IANA Considerations</a>
      </h2>
<div id="section.iana.dc">
<section id="section-5.1">
        <h3 id="name-subprotocol-identifier-clue">
<a href="#section-5.1" class="section-number selfRef">5.1. </a><a href="#name-subprotocol-identifier-clue" class="section-name selfRef">Subprotocol Identifier "clue"</a>
        </h3>
<p id="section-5.1-1">
        This document adds the subprotocol identifier "clue" to the "WebSocket Subprotocol Name Registry"
        as follows:<a href="#section-5.1-1" class="pilcrow">¶</a></p>
<span id="name-registration-of-clue-value"></span><div id="clue-reg">
<table class="center" id="table-3">
          <caption>
<a href="#table-3" class="selfRef">Table 3</a>:
<a href="#name-registration-of-clue-value" class="selfRef">Registration of 'clue' Value</a>
          </caption>
<tbody>
            <tr>
              <td class="text-left" rowspan="1" colspan="1">Subprotocol Identifier</td>
              <td class="text-left" rowspan="1" colspan="1">clue</td>
            </tr>
            <tr>
              <td class="text-left" rowspan="1" colspan="1">Subprotocol Common Name</td>
              <td class="text-left" rowspan="1" colspan="1">CLUE</td>
            </tr>
            <tr>
              <td class="text-left" rowspan="1" colspan="1">Subprotocol Definition</td>
              <td class="text-left" rowspan="1" colspan="1">RFC 8850</td>
            </tr>
            <tr>
              <td class="text-left" rowspan="1" colspan="1">Reference</td>
              <td class="text-left" rowspan="1" colspan="1">RFC 8850</td>
            </tr>
          </tbody>
        </table>
</div>
</section>
</div>
</section>
</div>
<section id="section-6">
      <h2 id="name-references">
<a href="#section-6" class="section-number selfRef">6. </a><a href="#name-references" class="section-name selfRef">References</a>
      </h2>
<section id="section-6.1">
        <h3 id="name-normative-references">
<a href="#section-6.1" class="section-number selfRef">6.1. </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" class="refDate">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>
<dd class="break"></dd>
<dt id="RFC3261">[RFC3261]</dt>
        <dd>
<span class="refAuthor">Rosenberg, J.</span><span class="refAuthor">, Schulzrinne, H.</span><span class="refAuthor">, Camarillo, G.</span><span class="refAuthor">, Johnston, A.</span><span class="refAuthor">, Peterson, J.</span><span class="refAuthor">, Sparks, R.</span><span class="refAuthor">, Handley, M.</span><span class="refAuthor">, and E. Schooler</span>, <span class="refTitle">"SIP: Session Initiation Protocol"</span>, <span class="seriesInfo">RFC 3261</span>, <span class="seriesInfo">DOI 10.17487/RFC3261</span>, <time datetime="2002-06" class="refDate">June 2002</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc3261">https://www.rfc-editor.org/info/rfc3261</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC3264">[RFC3264]</dt>
        <dd>
<span class="refAuthor">Rosenberg, J.</span><span class="refAuthor"> and H. Schulzrinne</span>, <span class="refTitle">"An Offer/Answer Model with Session Description Protocol (SDP)"</span>, <span class="seriesInfo">RFC 3264</span>, <span class="seriesInfo">DOI 10.17487/RFC3264</span>, <time datetime="2002-06" class="refDate">June 2002</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc3264">https://www.rfc-editor.org/info/rfc3264</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC4566">[RFC4566]</dt>
        <dd>
<span class="refAuthor">Handley, M.</span><span class="refAuthor">, Jacobson, V.</span><span class="refAuthor">, and C. Perkins</span>, <span class="refTitle">"SDP: Session Description Protocol"</span>, <span class="seriesInfo">RFC 4566</span>, <span class="seriesInfo">DOI 10.17487/RFC4566</span>, <time datetime="2006-07" class="refDate">July 2006</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc4566">https://www.rfc-editor.org/info/rfc4566</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC4960">[RFC4960]</dt>
        <dd>
<span class="refAuthor">Stewart, R., Ed.</span>, <span class="refTitle">"Stream Control Transmission Protocol"</span>, <span class="seriesInfo">RFC 4960</span>, <span class="seriesInfo">DOI 10.17487/RFC4960</span>, <time datetime="2007-09" class="refDate">September 2007</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc4960">https://www.rfc-editor.org/info/rfc4960</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC5061">[RFC5061]</dt>
        <dd>
<span class="refAuthor">Stewart, R.</span><span class="refAuthor">, Xie, Q.</span><span class="refAuthor">, Tuexen, M.</span><span class="refAuthor">, Maruyama, S.</span><span class="refAuthor">, and M. Kozuka</span>, <span class="refTitle">"Stream Control Transmission Protocol (SCTP) Dynamic Address Reconfiguration"</span>, <span class="seriesInfo">RFC 5061</span>, <span class="seriesInfo">DOI 10.17487/RFC5061</span>, <time datetime="2007-09" class="refDate">September 2007</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc5061">https://www.rfc-editor.org/info/rfc5061</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC6525">[RFC6525]</dt>
        <dd>
<span class="refAuthor">Stewart, R.</span><span class="refAuthor">, Tuexen, M.</span><span class="refAuthor">, and P. Lei</span>, <span class="refTitle">"Stream Control Transmission Protocol (SCTP) Stream Reconfiguration"</span>, <span class="seriesInfo">RFC 6525</span>, <span class="seriesInfo">DOI 10.17487/RFC6525</span>, <time datetime="2012-02" class="refDate">February 2012</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc6525">https://www.rfc-editor.org/info/rfc6525</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC7496">[RFC7496]</dt>
        <dd>
<span class="refAuthor">Tuexen, M.</span><span class="refAuthor">, Seggelmann, R.</span><span class="refAuthor">, Stewart, R.</span><span class="refAuthor">, and S. Loreto</span>, <span class="refTitle">"Additional Policies for the Partially Reliable Stream Control Transmission Protocol Extension"</span>, <span class="seriesInfo">RFC 7496</span>, <span class="seriesInfo">DOI 10.17487/RFC7496</span>, <time datetime="2015-04" class="refDate">April 2015</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc7496">https://www.rfc-editor.org/info/rfc7496</a>&gt;</span>. </dd>
<dd class="break"></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" class="refDate">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>
<dd class="break"></dd>
<dt id="RFC8261">[RFC8261]</dt>
        <dd>
<span class="refAuthor">Tuexen, M.</span><span class="refAuthor">, Stewart, R.</span><span class="refAuthor">, Jesup, R.</span><span class="refAuthor">, and S. Loreto</span>, <span class="refTitle">"Datagram Transport Layer Security (DTLS) Encapsulation of SCTP Packets"</span>, <span class="seriesInfo">RFC 8261</span>, <span class="seriesInfo">DOI 10.17487/RFC8261</span>, <time datetime="2017-11" class="refDate">November 2017</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc8261">https://www.rfc-editor.org/info/rfc8261</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC8831">[RFC8831]</dt>
        <dd>
<span class="refAuthor">Jesup, R.</span><span class="refAuthor">, Loreto, S.</span><span class="refAuthor">, and M. Tüxen</span>, <span class="refTitle">"WebRTC Data Channels"</span>, <span class="seriesInfo">RFC 8831</span>, <span class="seriesInfo">DOI 10.17487/RFC8831</span>, <time datetime="2021-01" class="refDate">January 2021</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc8831">https://www.rfc-editor.org/info/rfc8831</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC8841">[RFC8841]</dt>
        <dd>
<span class="refAuthor">Holmberg, C.</span><span class="refAuthor">, Shpount, R.</span><span class="refAuthor">, Loreto, S.</span><span class="refAuthor">, and G. Camarillo</span>, <span class="refTitle">"Session Description Protocol (SDP) Offer/Answer Procedures for Stream Control Transmission Protocol (SCTP) over Datagram Transport Layer Security (DTLS) Transport"</span>, <span class="seriesInfo">RFC 8841</span>, <span class="seriesInfo">DOI 10.17487/RFC8841</span>, <time datetime="2021-01" class="refDate">January 2021</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc8841">https://www.rfc-editor.org/info/rfc8841</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC8864">[RFC8864]</dt>
      <dd>
<span class="refAuthor">Drage, K.</span><span class="refAuthor">, Makaraju, M.</span><span class="refAuthor">, Ejzak, R.</span><span class="refAuthor">, Marcon, J.</span><span class="refAuthor">, and R. Even, Ed.</span>, <span class="refTitle">"Negotiation Data Channels Using the Session Description Protocol (SDP)"</span>, <span class="seriesInfo">RFC 8864</span>, <span class="seriesInfo">DOI 10.17487/RFC8864</span>, <time datetime="2021-01" class="refDate">January 2021</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc8864">https://www.rfc-editor.org/info/rfc8864</a>&gt;</span>. </dd>
<dd class="break"></dd>
</dl>
</section>
<section id="section-6.2">
        <h3 id="name-informative-references">
<a href="#section-6.2" class="section-number selfRef">6.2. </a><a href="#name-informative-references" class="section-name selfRef">Informative References</a>
        </h3>
<dl class="references">
<dt id="RFC3758">[RFC3758]</dt>
        <dd>
<span class="refAuthor">Stewart, R.</span><span class="refAuthor">, Ramalho, M.</span><span class="refAuthor">, Xie, Q.</span><span class="refAuthor">, Tuexen, M.</span><span class="refAuthor">, and P. Conrad</span>, <span class="refTitle">"Stream Control Transmission Protocol (SCTP) Partial Reliability Extension"</span>, <span class="seriesInfo">RFC 3758</span>, <span class="seriesInfo">DOI 10.17487/RFC3758</span>, <time datetime="2004-05" class="refDate">May 2004</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc3758">https://www.rfc-editor.org/info/rfc3758</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC8445">[RFC8445]</dt>
        <dd>
<span class="refAuthor">Keranen, A.</span><span class="refAuthor">, Holmberg, C.</span><span class="refAuthor">, and J. Rosenberg</span>, <span class="refTitle">"Interactive Connectivity Establishment (ICE): A Protocol for Network Address Translator (NAT) Traversal"</span>, <span class="seriesInfo">RFC 8445</span>, <span class="seriesInfo">DOI 10.17487/RFC8445</span>, <time datetime="2018-07" class="refDate">July 2018</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc8445">https://www.rfc-editor.org/info/rfc8445</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC8832">[RFC8832]</dt>
        <dd>
<span class="refAuthor">Jesup, R.</span><span class="refAuthor">, Loreto, S.</span><span class="refAuthor">, and M. Tüxen</span>, <span class="refTitle">"WebRTC Data Channel Establishment Protocol"</span>, <span class="seriesInfo">RFC 8832</span>, <span class="seriesInfo">DOI 10.17487/RFC8832</span>, <time datetime="2021-01" class="refDate">January 2021</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc8832">https://www.rfc-editor.org/info/rfc8832</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC8847">[RFC8847]</dt>
        <dd>
<span class="refAuthor">Presta, R.</span><span class="refAuthor"> and S P. Romano</span>, <span class="refTitle">"Protocol for Controlling Multiple Streams for Telepresence (CLUE)"</span>, <span class="seriesInfo">RFC 8847</span>, <span class="seriesInfo">DOI 10.17487/RFC8847</span>, <time datetime="2021-01" class="refDate">January 2021</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc8847">https://www.rfc-editor.org/info/rfc8847</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC8848">[RFC8848]</dt>
      <dd>
<span class="refAuthor">Hanton, R.</span><span class="refAuthor">, Kyzivat, P.</span><span class="refAuthor">, Xiao, L.</span><span class="refAuthor">, and C. Groves</span>, <span class="refTitle">"Session Signaling for Controlling Multiple Streams for Telepresence (CLUE)"</span>, <span class="seriesInfo">RFC 8848</span>, <span class="seriesInfo">DOI 10.17487/RFC8848</span>, <time datetime="2021-01" class="refDate">January 2021</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc8848">https://www.rfc-editor.org/info/rfc8848</a>&gt;</span>. </dd>
<dd class="break"></dd>
</dl>
</section>
</section>
<section id="section-appendix.a">
      <h2 id="name-acknowledgements">
<a href="#name-acknowledgements" class="section-name selfRef">Acknowledgements</a>
      </h2>
<p id="section-appendix.a-1">
        Thanks to <span class="contact-name">Paul Kyzivat</span>,
        <span class="contact-name">Christian Groves</span>, and
        <span class="contact-name">Mark Duckworth</span> for comments
        on this document.<a href="#section-appendix.a-1" class="pilcrow">¶</a></p>
</section>
<div id="authors-addresses">
<section id="section-appendix.b">
      <h2 id="name-authors-address">
<a href="#name-authors-address" class="section-name selfRef">Author's Address</a>
      </h2>
<address class="vcard">
        <div dir="auto" class="left"><span class="fn nameRole">Christer Holmberg</span></div>
<div dir="auto" class="left"><span class="org">Ericsson</span></div>
<div dir="auto" class="left"><span class="street-address">Hirsalantie 11</span></div>
<div dir="auto" class="left">FI-<span class="postal-code">02420</span> <span class="locality">Jorvas</span>
</div>
<div dir="auto" class="left"><span class="country-name">Finland</span></div>
<div class="email">
<span>Email:</span>
<a href="mailto:christer.holmberg@ericsson.com" class="email">christer.holmberg@ericsson.com</a>
</div>
</address>
</section>
</div>
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