File: rfc8902.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 8902: TLS Authentication Using Intelligent Transport System (ITS) Certificates</title>
<meta content="Mounira Msahli" name="author">
<meta content="Nancy Cam-Winget" name="author">
<meta content="William Whyte" name="author">
<meta content="Ahmed Serhrouchni" name="author">
<meta content="Houda Labiod" name="author">
<meta content="
       
  
  The IEEE and ETSI have specified a type of end-entity certificate. This document defines an experimental change to TLS to support IEEE/ETSI certificate types to authenticate TLS entities.  
    " name="description">
<meta content="xml2rfc 3.2.1" name="generator">
<meta content="TLS" name="keyword">
<meta content="Intelligent Transport System (ITS) Certificates" name="keyword">
<meta content="IEEE" name="keyword">
<meta content="ETSI" name="keyword">
<meta content="8902" name="rfc.number">
<!-- Generator version information:
  xml2rfc 3.2.1
    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="rfc8902.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;
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h5, h6 {
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}
#n-copyright-notice {
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  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 {
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  border: 1px solid #eee;
  border-radius: 3px;
  padding: 1em 1em 0;
  margin-bottom: 1.5em;
}
.alignRight.art-text pre {
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}
.alignRight {
  margin: 1em 0;
}
.alignRight > *:first-child {
  border: none;
  margin: 0;
  float: right;
  clear: both;
}
.alignRight > *:nth-child(2) {
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  display: block;
  border: none;
}
svg {
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}
.alignCenter.art-text {
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  border: 1px solid #eee;
  border-radius: 3px;
  padding: 1em 1em 0;
  margin-bottom: 1.5em;
}
.alignCenter.art-text pre {
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}
.alignCenter {
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}
.alignCenter > *:first-child {
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  /* 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 {
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}
li {
  margin: 0 0 0.25em 0;
}
.ulCompact li {
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}
ul.empty, .ulEmpty {
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}
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 {
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}
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;
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}
tr:nth-child(2n+1) > td {
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}
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 {
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}

.ears tfoot .left {
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}

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

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

@page :first {
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  @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;
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  @bottom-right {
      content: '[Page ' counter(page) ']';
      vertical-align: top;
      border-top: solid 1px #ccc;
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  */

}

/* 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;
}
/* 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 */
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<link href="https://dx.doi.org/10.17487/rfc8902" rel="alternate">
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<table class="ears">
<thead><tr>
<td class="left">RFC 8902</td>
<td class="center">IEEE and ETSI Certificate Types for TLS</td>
<td class="right">September 2020</td>
</tr></thead>
<tfoot><tr>
<td class="left">Msahli, et al.</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">Independent Submission</dd>
<dt class="label-rfc">RFC:</dt>
<dd class="rfc"><a href="https://www.rfc-editor.org/rfc/rfc8902" class="eref">8902</a></dd>
<dt class="label-category">Category:</dt>
<dd class="category">Experimental</dd>
<dt class="label-published">Published:</dt>
<dd class="published">
<time datetime="2020-09" class="published">September 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">M. Msahli, <span class="editor">Ed.</span>
</div>
<div class="org">Telecom Paris</div>
</div>
<div class="author">
      <div class="author-name">N. Cam-Winget, <span class="editor">Ed.</span>
</div>
<div class="org">Cisco</div>
</div>
<div class="author">
      <div class="author-name">W. Whyte, <span class="editor">Ed.</span>
</div>
<div class="org">Qualcomm</div>
</div>
<div class="author">
      <div class="author-name">A. Serhrouchni</div>
<div class="org">Telecom Paris</div>
</div>
<div class="author">
      <div class="author-name">H. Labiod</div>
<div class="org">Telecom Paris</div>
</div>
</dd>
</dl>
</div>
<h1 id="rfcnum">RFC 8902</h1>
<h1 id="title">TLS Authentication Using Intelligent Transport System (ITS) Certificates</h1>
<section id="section-abstract">
      <h2 id="abstract"><a href="#abstract" class="selfRef">Abstract</a></h2>
<p id="section-abstract-1">
  
  The IEEE and ETSI have specified a type of end-entity certificate. This document defines an experimental change to TLS to support IEEE/ETSI certificate types to authenticate TLS 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 is a contribution to the RFC Series,
            independently of any other RFC stream.  The RFC Editor has chosen to publish this
            document at its discretion and makes no statement about its value
            for implementation or deployment.  Documents approved for publication
            by the RFC Editor are not 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/rfc8902">https://www.rfc-editor.org/info/rfc8902</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) 2020 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.<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="ulEmpty toc compact">
<li class="ulEmpty toc compact" 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>
<ul class="ulEmpty toc compact">
<li class="ulEmpty toc compact" id="section-toc.1-1.1.2.1">
                <p id="section-toc.1-1.1.2.1.1" class="keepWithNext"><a href="#section-1.1" class="xref">1.1</a>.  <a href="#name-experiment-overview" class="xref">Experiment Overview</a><a href="#section-toc.1-1.1.2.1.1" class="pilcrow">¶</a></p>
</li>
            </ul>
</li>
          <li class="ulEmpty toc compact" 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-requirements-terminology" class="xref">Requirements Terminology</a><a href="#section-toc.1-1.2.1" class="pilcrow">¶</a></p>
</li>
          <li class="ulEmpty toc compact" 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-extension-overview" class="xref">Extension Overview</a><a href="#section-toc.1-1.3.1" class="pilcrow">¶</a></p>
</li>
          <li class="ulEmpty toc compact" 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-tls-client-and-server-hands" class="xref">TLS Client and Server Handshake</a><a href="#section-toc.1-1.4.1" class="pilcrow">¶</a></p>
<ul class="ulEmpty toc compact">
<li class="ulEmpty toc compact" 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-client-hello" class="xref">Client Hello</a><a href="#section-toc.1-1.4.2.1.1" class="pilcrow">¶</a></p>
</li>
              <li class="ulEmpty toc compact" 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-server-hello" class="xref">Server Hello</a><a href="#section-toc.1-1.4.2.2.1" class="pilcrow">¶</a></p>
</li>
            </ul>
</li>
          <li class="ulEmpty toc compact" 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-certificate-verification" class="xref">Certificate Verification</a><a href="#section-toc.1-1.5.1" class="pilcrow">¶</a></p>
</li>
          <li class="ulEmpty toc compact" 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-examples" class="xref">Examples</a><a href="#section-toc.1-1.6.1" class="pilcrow">¶</a></p>
<ul class="ulEmpty toc compact">
<li class="ulEmpty toc compact" 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-tls-server-and-tls-client-u" class="xref">TLS Server and TLS Client Use the ITS Certificate</a><a href="#section-toc.1-1.6.2.1.1" class="pilcrow">¶</a></p>
</li>
              <li class="ulEmpty toc compact" 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-tls-client-uses-the-its-cer" class="xref">TLS Client Uses the ITS Certificate and TLS Server Uses the X.509 Certificate</a><a href="#section-toc.1-1.6.2.2.1" class="pilcrow">¶</a></p>
</li>
            </ul>
</li>
          <li class="ulEmpty toc compact" 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>
<ul class="ulEmpty toc compact">
<li class="ulEmpty toc compact" id="section-toc.1-1.7.2.1">
                <p id="section-toc.1-1.7.2.1.1"><a href="#section-7.1" class="xref">7.1</a>.  <a href="#name-securely-obtaining-certific" class="xref">Securely Obtaining Certificates from an Online Repository</a><a href="#section-toc.1-1.7.2.1.1" class="pilcrow">¶</a></p>
</li>
              <li class="ulEmpty toc compact" id="section-toc.1-1.7.2.2">
                <p id="section-toc.1-1.7.2.2.1"><a href="#section-7.2" class="xref">7.2</a>.  <a href="#name-expiry-of-certificates" class="xref">Expiry of Certificates</a><a href="#section-toc.1-1.7.2.2.1" class="pilcrow">¶</a></p>
</li>
              <li class="ulEmpty toc compact" id="section-toc.1-1.7.2.3">
                <p id="section-toc.1-1.7.2.3.1"><a href="#section-7.3" class="xref">7.3</a>.  <a href="#name-algorithms-and-cryptographi" class="xref">Algorithms and Cryptographic Strength</a><a href="#section-toc.1-1.7.2.3.1" class="pilcrow">¶</a></p>
</li>
              <li class="ulEmpty toc compact" id="section-toc.1-1.7.2.4">
                <p id="section-toc.1-1.7.2.4.1"><a href="#section-7.4" class="xref">7.4</a>.  <a href="#name-interpreting-its-certificat" class="xref">Interpreting ITS Certificate Permissions</a><a href="#section-toc.1-1.7.2.4.1" class="pilcrow">¶</a></p>
</li>
              <li class="ulEmpty toc compact" id="section-toc.1-1.7.2.5">
                <p id="section-toc.1-1.7.2.5.1"><a href="#section-7.5" class="xref">7.5</a>.  <a href="#name-psid-and-pdufunctionaltype-" class="xref">Psid and Pdufunctionaltype in CertificateVerify</a><a href="#section-toc.1-1.7.2.5.1" class="pilcrow">¶</a></p>
</li>
            </ul>
</li>
          <li class="ulEmpty toc compact" 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-privacy-considerations" class="xref">Privacy Considerations</a><a href="#section-toc.1-1.8.1" class="pilcrow">¶</a></p>
</li>
          <li class="ulEmpty toc compact" 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-iana-considerations" class="xref">IANA Considerations</a><a href="#section-toc.1-1.9.1" class="pilcrow">¶</a></p>
</li>
          <li class="ulEmpty toc compact" id="section-toc.1-1.10">
            <p id="section-toc.1-1.10.1"><a href="#section-10" class="xref">10</a>. <a href="#name-normative-references" class="xref">Normative References</a><a href="#section-toc.1-1.10.1" class="pilcrow">¶</a></p>
</li>
          <li class="ulEmpty toc compact" id="section-toc.1-1.11">
            <p id="section-toc.1-1.11.1"><a href="#section-appendix.a" class="xref"></a><a href="#name-acknowledgements" class="xref">Acknowledgements</a><a href="#section-toc.1-1.11.1" class="pilcrow">¶</a></p>
</li>
          <li class="ulEmpty toc compact" id="section-toc.1-1.12">
            <p id="section-toc.1-1.12.1"><a href="#section-appendix.b" 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>
</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">The TLS protocol <span>[<a href="#RFC8446" class="xref">RFC8446</a>]</span> allows the use of X.509
      certificates and raw public keys to authenticate servers and
      clients. This document describes an experimental extension following the
      procedures laid out by <span>[<a href="#RFC7250" class="xref">RFC7250</a>]</span> to support use of the certificate
      format specified by the IEEE in <span>[<a href="#IEEE1609.2" class="xref">IEEE1609.2</a>]</span> and profiled by the
      European Telecommunications Standards Institute (ETSI) in <span>[<a href="#TS103097" class="xref">TS103097</a>]</span>. These standards specify secure communications in
      vehicular environments. These certificates are referred to in this
      document as Intelligent Transport Systems (ITS) Certificates.<a href="#section-1-1" class="pilcrow">¶</a></p>
<p id="section-1-2">The certificate types are optimized for bandwidth and processing time
      to support delay-sensitive applications and also to provide both
      authentication and authorization information to enable fast access
      control decisions in ad hoc networks found in Intelligent
      Transport Systems (ITS). The standards specify different types of
      certificates to support a full Public Key Infrastructure (PKI)
      specification; the certificates to be used in this context are
      end-entity certificates, i.e., certificates that have the IEEE 1609.2
      appPermissions field present.<a href="#section-1-2" class="pilcrow">¶</a></p>
<p id="section-1-3">Use of ITS certificates is becoming widespread in the ITS
      setting. ITS communications, in practice, make heavy use of 10 MHz
      channels with a typical throughput of 6 Mbps. (The 802.11OCB modulation
      that gives this throughput is not the one that gives the highest
      throughput, but it provides for a robust signal over a range up to
      300-500 m, which is the "sweet spot" communications range for ITS
      operations like collision avoidance). The compact nature of ITS
      certificates as opposed to X.509 certificates makes them appropriate for
      this setting.<a href="#section-1-3" class="pilcrow">¶</a></p>
<p id="section-1-4">The ITS certificates are also suited to the machine-to-machine (M2M)
      ad hoc network setting because their direct encoding of permissions (see
      <a href="#ITS-permissions" class="xref">Section 7.4</a>) allows a receiver to make an immediate
      accept/deny decision about an incoming message without having to refer
      to a remote identity and access management server. The EU has committed
      to the use of ITS certificates in Cooperative Intelligent Transport
      Systems deployments. A multi-year project developed a certificate policy
      for the use of ITS certificates, including a specification of how
      different root certificates can be trusted across the system (hosted at
      &lt;<span><a href="https://ec.europa.eu/transport/themes/its/c-its_en">https://ec.europa.eu/transport/themes/its/c-its_en</a></span>&gt;,
      direct link at &lt;<span><a href="https://ec.europa.eu/transport/sites/transport/files/c-its_certificate_policy_release_1.pdf">https://ec.europa.eu/transport/sites/transport/files/c-its_certificate_policy_release_1.pdf</a></span>&gt;).<a href="#section-1-4" class="pilcrow">¶</a></p>
<p id="section-1-5"> The EU has committed funding for the first five years of operation
      of the top-level Trust List Manager entity, enabling organizations such
      as motor vehicle original equipment manufacturers (OEMs) and national
      road authorities to create root certificate authorities (CAs) and have
      them trusted. In the US, the US Department of Transportation (USDOT)
      published a proposed regulation, active as of late 2019 though not
      rapidly progressing, requiring all light vehicles in the US to implement
      vehicle-to-everything (V2X) communications, including the use of ITS
      certificates (available at &lt;<span><a href="https://www.federalregister.gov/documents/2017/01/12/2016-31059/federal-motor-vehicle-safety-standards-v2v-communications">https://www.federalregister.gov/documents/2017/01/12/2016-31059/federal-motor-vehicle-safety-standards-v2v-communications</a></span>&gt;). As
      of 2019, ITS deployments across the US, Europe, and Australia were using
      ITS certificates. Volkswagen has committed to deploying V2X using ITS
      certificates. New York, Tampa, and Wyoming are deploying traffic
      management systems using ITS certificates. GM deployed V2X in the
      Cadillac CTS, using ITS certificates.<a href="#section-1-5" class="pilcrow">¶</a></p>
<p id="section-1-6"> ITS certificates are also used in a number of standards that build
      on top of the foundational IEEE and ETSI standards, particularly the
      Society of Automobile Engineers (SAE) J2945/x series of standards for
      applications and ISO 21177 <span>[<a href="#ISO21177" class="xref">ISO21177</a>]</span>, which builds a framework for exchanging
      multiple authentication tokens on top of the TLS variant specified in
      this document.<a href="#section-1-6" class="pilcrow">¶</a></p>
<section id="section-1.1">
        <h3 id="name-experiment-overview">
<a href="#section-1.1" class="section-number selfRef">1.1. </a><a href="#name-experiment-overview" class="section-name selfRef">Experiment Overview</a>
        </h3>
<p id="section-1.1-1">This document describes an experimental extension to the TLS
        security model. It uses a form of certificate that has not previously
        been used in the Internet.  Systems using this Experimental approach
        are segregated from systems using standard TLS by the use of a new
        certificate type value, reserved through IANA (see <a href="#IANA" class="xref">Section 9</a>).  An implementation of TLS that is not involved in
        the Experiment will not recognize this new certificate type and will
        not participate in the experiment; TLS sessions will either negotiate
        the use of existing X.509 certificates or fail to be established.<a href="#section-1.1-1" class="pilcrow">¶</a></p>
<p id="section-1.1-2">This extension has been encouraged by stakeholders in the
        Cooperative ITS community in order to support ITS use-case
        deployment, and it is anticipated that its use will be widespread.<a href="#section-1.1-2" class="pilcrow">¶</a></p>
</section>
</section>
<section id="section-2">
      <h2 id="name-requirements-terminology">
<a href="#section-2" class="section-number selfRef">2. </a><a href="#name-requirements-terminology" class="section-name selfRef">Requirements Terminology</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>
</section>
<section id="section-3">
      <h2 id="name-extension-overview">
<a href="#section-3" class="section-number selfRef">3. </a><a href="#name-extension-overview" class="section-name selfRef">Extension Overview</a>
      </h2>
<p id="section-3-1"> The TLS extensions "client_certificate_type" and
      "server_certificate_type" <span>[<a href="#RFC7250" class="xref">RFC7250</a>]</span> are used to negotiate
      the type of Certificate messages used in TLS to authenticate the server
      and, optionally, the client. Using separate extensions allows for mixed
      deployments where the client and server can use certificates of different types. It is expected that ITS
 deployments will see both peers using ITS certificates due to the homogeneity of the ecosystem, but there is no barrier at a technical level that prevents mixed certificate usage. This document defines a new certificate type, 1609Dot2, for usage with
TLS 1.3. The updated CertificateType enumeration and corresponding addition to the CertificateEntry structure are shown below. CertificateType values are sent in the "server_certificate_type" and "client_certificate_type" extensions, and the CertificateEntry
 structures are included in the certificate chain sent in the Certificate message.
    
 In the case of TLS 1.3, the "client_certificate_type" <span class="bcp14">SHALL</span> contain a list of supported certificate types proposed by the client as provided in the figure below:<a href="#section-3-1" class="pilcrow">¶</a></p>
<div id="section-3-2">
<pre class="sourcecode">
  /* Managed by IANA */
   enum {
       X509(0),
       RawPublicKey(2),
       1609Dot2(3),
       (255)
   } CertificateType;

   struct {
       select (certificate_type) {

           /* certificate type defined in this document.*/
            case 1609Dot2:
            opaque cert_data&lt;1..2^24-1&gt;;

            /* RawPublicKey defined in RFC 7250*/
           case RawPublicKey:
           opaque ASN.1_subjectPublicKeyInfo&lt;1..2^24-1&gt;;

           /* X.509 certificate defined in RFC 8446*/
           case X.509:
           opaque cert_data&lt;1..2^24-1&gt;;

            };

          Extension extensions&lt;0..2^16-1&gt;;
      } CertificateEntry;
</pre><a href="#section-3-2" class="pilcrow">¶</a>
</div>
<p id="section-3-3"> As per <span>[<a href="#RFC7250" class="xref">RFC7250</a>]</span>, the server processes the received
      [endpoint]_certificate_type extension(s) and selects one of the offered
      certificate types, returning the negotiated value in its
      EncryptedExtensions (TLS 1.3) message. Note that there is no requirement
      for the negotiated value to be the same in client_certificate_type and
      server_certificate_type extensions sent in the same message.<a href="#section-3-3" class="pilcrow">¶</a></p>
</section>
<section id="section-4">
      <h2 id="name-tls-client-and-server-hands">
<a href="#section-4" class="section-number selfRef">4. </a><a href="#name-tls-client-and-server-hands" class="section-name selfRef">TLS Client and Server Handshake</a>
      </h2>
<p id="section-4-1"><a href="#msg_flow" class="xref">Figure 1</a> shows the handshake message flow for a full TLS 1.3 handshake negotiating both certificate types.<a href="#section-4-1" class="pilcrow">¶</a></p>
<span id="name-message-flow-with-certifica"></span><div id="msg_flow">
<figure id="figure-1">
        <div class="artwork art-text alignLeft" id="section-4-2.1">
<pre>
  Client                                           Server

Key  ^ ClientHello
Exch | + server_certificate_type*
     | + client_certificate_type*
     | + key_share*
     v + signature_algorithms*       --------&gt;
                                                ServerHello  ^ Key
                                               + key_share*  v Exch
                                      {EncryptedExtensions}  ^ Server
                                 {+ server_certificate_type*}| Params
                                 {+ client_certificate_type*}|
                                      {CertificateRequest*}  v
                                             {Certificate*}  ^
                                       {CertificateVerify*}  | Auth
                                                 {Finished}  v
                              &lt;-------  [Application Data*]
     ^ {Certificate*}
Auth | {CertificateVerify*}
     v {Finished}             --------&gt;
       [Application Data]     &lt;-------&gt;  [Application Data]
              +  Indicates noteworthy extensions sent in the
                 previously noted message.

              *  Indicates optional or situation-dependent
                 messages/extensions that are not always sent.

              {} Indicates messages protected using keys
                 derived from a [sender]_handshake_traffic_secret.

              [] Indicates messages protected using keys
                 derived from [sender]_application_traffic_secret_N.
</pre>
</div>
<figcaption><a href="#figure-1" class="selfRef">Figure 1</a>:
<a href="#name-message-flow-with-certifica" class="selfRef">Message Flow with Certificate Type Extension for Full TLS 1.3 Handshake</a>
        </figcaption></figure>
</div>
<p id="section-4-3"> In the case of TLS 1.3, in order to negotiate the support of ITS
      certificate-based authentication, clients and servers include the
      extension of type "client_certificate_type" and
      "server_certificate_type" in the extended Client Hello and
      "EncryptedExtensions".<a href="#section-4-3" class="pilcrow">¶</a></p>
<section id="section-4.1">
        <h3 id="name-client-hello">
<a href="#section-4.1" class="section-number selfRef">4.1. </a><a href="#name-client-hello" class="section-name selfRef">Client Hello</a>
        </h3>
<p id="section-4.1-1">In order to indicate the support of ITS certificates, a client
        <span class="bcp14">MUST</span> include an extension of type
        "client_certificate_type" or "server_certificate_type" in the extended
        Client Hello message as described in <span><a href="https://www.rfc-editor.org/rfc/rfc8446#section-4.1.2" class="relref">Section 4.1.2</a> of [<a href="#RFC8446" class="xref">RFC8446</a>]</span> (TLS 1.3).<a href="#section-4.1-1" class="pilcrow">¶</a></p>
<p id="section-4.1-2">For TLS 1.3, the rules for when the Client Certificate and
        CertificateVerify messages appear are as follows:<a href="#section-4.1-2" class="pilcrow">¶</a></p>
<ul class="normal">
<li class="normal" id="section-4.1-3.1">The client's Certificate message is present if and only if
          the server sent a CertificateRequest message.<a href="#section-4.1-3.1" class="pilcrow">¶</a>
</li>
          <li class="normal" id="section-4.1-3.2">The client's CertificateVerify message is present if and only if the client's Certificate message is present and contains a non-empty certificate_list.<a href="#section-4.1-3.2" class="pilcrow">¶</a>
</li>
        </ul>
<p id="section-4.1-4"> For maximum compatibility, all implementations
        <span class="bcp14">SHOULD</span> be prepared to handle "potentially" extraneous
        certificates and arbitrary orderings from any TLS version, with the
        exception of the end-entity certificate, which <span class="bcp14">MUST</span> be
        first.<a href="#section-4.1-4" class="pilcrow">¶</a></p>
</section>
<section id="section-4.2">
        <h3 id="name-server-hello">
<a href="#section-4.2" class="section-number selfRef">4.2. </a><a href="#name-server-hello" class="section-name selfRef">Server Hello</a>
        </h3>
<p id="section-4.2-1"> When the server receives the Client Hello containing the client_certificate_type extension and/or the server_certificate_type extension, the following scenarios are possible:<a href="#section-4.2-1" class="pilcrow">¶</a></p>
<ul class="normal">
<li class="normal" id="section-4.2-2.1">If both the client and server indicate support for the ITS
          certificate type, the server <span class="bcp14">MAY</span> select the first
          (most preferred) certificate type from the client's list that is
          supported by both peers.<a href="#section-4.2-2.1" class="pilcrow">¶</a>
</li>
          <li class="normal" id="section-4.2-2.2">The server does not support any of the proposed certificate
          types and terminates the session with a fatal alert of type
          "unsupported_certificate".<a href="#section-4.2-2.2" class="pilcrow">¶</a>
</li>
          <li class="normal" id="section-4.2-2.3">The server supports the certificate types specified in this
          document. In this case, it <span class="bcp14">MAY</span> respond with a
          certificate of this type. It <span class="bcp14">MAY</span> also include the
          client_certificate_type extension in Encrypted Extension.  Then, the
          server requests a certificate from the client (via the
          CertificateRequest message).<a href="#section-4.2-2.3" class="pilcrow">¶</a>
</li>
        </ul>
<p id="section-4.2-3">The certificates in the TLS client or server certificate chain
        <span class="bcp14">MAY</span> be sent as part of the handshake,
        <span class="bcp14">MAY</span> be obtained from an online repository, or
        might already be known to and cached at the endpoint.  If the
        handshake does not contain all the certificates in the chain, and the
        endpoint cannot access the repository and does not already know the
        certificates from the chain, then it <span class="bcp14">SHALL</span> reject the
        other endpoint's certificate and close the connection. Protocols to
        support retrieving certificates from a repository are specified in
        ETSI <span>[<a href="#TS102941" class="xref">TS102941</a>]</span>.<a href="#section-4.2-3" class="pilcrow">¶</a></p>
</section>
</section>
<section id="section-5">
      <h2 id="name-certificate-verification">
<a href="#section-5" class="section-number selfRef">5. </a><a href="#name-certificate-verification" class="section-name selfRef">Certificate Verification</a>
      </h2>
<p id="section-5-1">Verification of an ITS certificate or certificate chain is described in
  section 5.1 of <span>[<a href="#IEEE1609.2" class="xref">IEEE1609.2</a>]</span>. In the case of
  TLS 1.3, and when the certificate_type is 1609.2, the CertificateVerify
  contents and processing are different than for the CertificateVerify message
  specified for other values of certificate_type in <span>[<a href="#RFC8446" class="xref">RFC8446</a>]</span>. In this case, the CertificateVerify message contains an
  Ieee1609Dot2Data encoded with Canonical Octet Encoding Rules (OER)
  <span>[<a href="#ITU-TX.696" class="xref">ITU-TX.696</a>]</span>
  of type signed as specified in <span>[<a href="#IEEE1609.2" class="xref">IEEE1609.2</a>]</span> and <span>[<a href="#IEEE1609.2b" class="xref">IEEE1609.2b</a>]</span>, where:<a href="#section-5-1" class="pilcrow">¶</a></p>
<ul class="normal">
<li class="normal" id="section-5-2.1">payload contains an extDataHash containing the SHA-256 hash of
        the data that the signature is calculated over. This is identical to the
        data that the signature is calculated over in standard TLS, which
        is reproduced below for clarity.<a href="#section-5-2.1" class="pilcrow">¶</a>
</li>
        <li class="normal" id="section-5-2.2">headerInfo.psid indicates the application
        activity that the certificate is authorizing.<a href="#section-5-2.2" class="pilcrow">¶</a>
</li>
        <li class="normal" id="section-5-2.3">headerInfo.generationTime is the time at which the data structure was generated.<a href="#section-5-2.3" class="pilcrow">¶</a>
</li>
        <li class="normal" id="section-5-2.4">headerInfo.pduFunctionalType (as specified in <span>[<a href="#IEEE1609.2b" class="xref">IEEE1609.2b</a>]</span>)
        is present and is set equal to tlsHandshake (1).<a href="#section-5-2.4" class="pilcrow">¶</a>
</li>
      </ul>
<p id="section-5-3">

   All other fields in the headerInfo are omitted. The certificate
   appPermissions field <span class="bcp14">SHALL</span> be present and
   <span class="bcp14">SHALL</span> permit (as defined in <span>[<a href="#IEEE1609.2" class="xref">IEEE1609.2</a>]</span>)
   signing of PDUs with the PSID indicated in the HeaderInfo of the
   SignedData. If the application specification for that PSID requires Service
   Specific Permissions (SSP) for signing a pduFunctionalType of tlsHandshake,
   this SSP <span class="bcp14">SHALL</span> also be present. For more details on the use
   of PSID and SSP, see <span>[<a href="#IEEE1609.2" class="xref">IEEE1609.2</a>]</span>, clauses 5.1.1 and
   5.2.3.3.3. All other fields in the headerInfo are omitted.<a href="#section-5-3" class="pilcrow">¶</a></p>
<p id="section-5-4">The certificate appPermissions field <span class="bcp14">SHALL</span> be present and <span class="bcp14">SHALL</span>
      permit (as defined in <span>[<a href="#IEEE1609.2" class="xref">IEEE1609.2</a>]</span>) signing of PDUs with the PSID
      indicated in the HeaderInfo of the SignedData. If the application
      specification for that PSID requires Service Specific Permissions (SSP)
      for signing a pduFunctionalType of tlsHandshake, this SSP <span class="bcp14">SHALL</span> also be
      present.<a href="#section-5-4" class="pilcrow">¶</a></p>
<p id="section-5-5">The signature and verification are carried out as specified in <span>[<a href="#IEEE1609.2" class="xref">IEEE1609.2</a>]</span>.<a href="#section-5-5" class="pilcrow">¶</a></p>
<p id="section-5-6"> The input to the hash process is identical to the message input for
      TLS 1.3, as specified in <span><a href="https://www.rfc-editor.org/rfc/rfc8446#section-4.4.3" class="relref">Section 4.4.3</a> of [<a href="#RFC8446" class="xref">RFC8446</a>]</span>, consisting of pad, context string, separator, and
      content, where content is Transcript-Hash(Handshake Context,
      Certificate).<a href="#section-5-6" class="pilcrow">¶</a></p>
</section>
<section id="section-6">
      <h2 id="name-examples">
<a href="#section-6" class="section-number selfRef">6. </a><a href="#name-examples" class="section-name selfRef">Examples</a>
      </h2>
<p id="section-6-1">Some of the message-exchange examples are illustrated in Figures       
      <a href="#msg_fltw" class="xref">2</a> and <a href="#msg_fluw" class="xref">3</a>.<a href="#section-6-1" class="pilcrow">¶</a></p>
<section id="section-6.1">
        <h3 id="name-tls-server-and-tls-client-u">
<a href="#section-6.1" class="section-number selfRef">6.1. </a><a href="#name-tls-server-and-tls-client-u" class="section-name selfRef">TLS Server and TLS Client Use the ITS Certificate</a>
        </h3>
<p id="section-6.1-1">This section shows an example where the TLS client as well as the TLS server use ITS certificates. In consequence, both the 
server and the client populate the client_certificate_type and
server_certificate_type extension with the IEEE 1609 Dot 2 type as mentioned
in <a href="#msg_fltw" class="xref">Figure 2</a>.<a href="#section-6.1-1" class="pilcrow">¶</a></p>
<span id="name-tls-client-and-tls-server-u"></span><div id="msg_fltw">
<figure id="figure-2">
          <div class="artwork art-text alignLeft" id="section-6.1-2.1">
<pre>
   Client                                           Server

ClientHello,
client_certificate_type=1609Dot2,
server_certificate_type=1609Dot2,  --------&gt;    ServerHello,
                                       {EncryptedExtensions}
                          {client_certificate_type=1609Dot2}
                          {server_certificate_type=1609Dot2}
                                        {CertificateRequest}
                                               {Certificate}
                                         {CertificateVerify}
                                                  {Finished}
  {Certificate}          &lt;-------         [Application Data]
  {CertificateVerify}
  {Finished}             --------&gt;
  [Application Data]     &lt;-------&gt;        [Application Data]
</pre>
</div>
<figcaption><a href="#figure-2" class="selfRef">Figure 2</a>:
<a href="#name-tls-client-and-tls-server-u" class="selfRef">TLS Client and TLS Server Use the ITS Certificate</a>
          </figcaption></figure>
</div>
</section>
<section id="section-6.2">
        <h3 id="name-tls-client-uses-the-its-cer">
<a href="#section-6.2" class="section-number selfRef">6.2. </a><a href="#name-tls-client-uses-the-its-cer" class="section-name selfRef">TLS Client Uses the ITS Certificate and TLS Server Uses the X.509 Certificate</a>
        </h3>
<p id="section-6.2-1"> This example shows the TLS authentication, where the TLS client
        populates the server_certificate_type extension with the X.509
        certificate and raw public key type as presented in <a href="#msg_fluw" class="xref">Figure 3</a>. The client indicates its ability to receive and
        validate an X.509 certificate from the server. The server chooses the
        X.509 certificate to make its authentication with the client. This is
        applicable in the case of a raw public key supported by the server.<a href="#section-6.2-1" class="pilcrow">¶</a></p>
<span id="name-tls-client-uses-the-its-cert"></span><div id="msg_fluw">
<figure id="figure-3">
          <div class="artwork art-text alignLeft" id="section-6.2-2.1">
<pre>
Client                                           Server
ClientHello,
client_certificate_type=(1609Dot2),
server_certificate_type=(1609Dot2,
X509,RawPublicKey),         -----------&gt;         ServerHello,
                                        {EncryptedExtensions}
                           {client_certificate_type=1609Dot2}
                               {server_certificate_type=X509}
                                         {CertificateRequest}
                                                {Certificate}
                                          {CertificateVerify}
                                                   {Finished}
                            &lt;---------     [Application Data]
{Finished}                  ---------&gt;
[Application Data]          &lt;--------&gt;     [Application Data]
</pre>
</div>
<figcaption><a href="#figure-3" class="selfRef">Figure 3</a>:
<a href="#name-tls-client-uses-the-its-cert" class="selfRef">TLS Client Uses the ITS Certificate and TLS Server Uses the X.509 Certificate</a>
          </figcaption></figure>
</div>
</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">This section provides an overview of the basic security
      considerations that need to be taken into account before implementing
      the necessary security mechanisms. The security considerations described
      throughout <span>[<a href="#RFC8446" class="xref">RFC8446</a>]</span> apply here as
      well.<a href="#section-7-1" class="pilcrow">¶</a></p>
<section id="section-7.1">
        <h3 id="name-securely-obtaining-certific">
<a href="#section-7.1" class="section-number selfRef">7.1. </a><a href="#name-securely-obtaining-certific" class="section-name selfRef">Securely Obtaining Certificates from an Online Repository</a>
        </h3>
<p id="section-7.1-1">In particular, the certificates used to establish a secure connection <span class="bcp14">MAY</span> be obtained from an online repository. An online repository may be used to obtain the CA certificates in the chain of either participant in the secure session.
ETSI TS 102 941 <span>[<a href="#TS102941" class="xref">TS102941</a>]</span> provides a mechanism that can be used to securely obtain ITS certificates.<a href="#section-7.1-1" class="pilcrow">¶</a></p>
</section>
<section id="section-7.2">
        <h3 id="name-expiry-of-certificates">
<a href="#section-7.2" class="section-number selfRef">7.2. </a><a href="#name-expiry-of-certificates" class="section-name selfRef">Expiry of Certificates</a>
        </h3>
<p id="section-7.2-1">Conventions around certificate lifetime differ between ITS
        certificates and X.509 certificates, and in particular, ITS
        certificates may be relatively short lived compared with typical X.509
        certificates. A party to a TLS session that accepts ITS certificates
        <span class="bcp14">MUST</span> check the expiry time in the received ITS
        certificate and <span class="bcp14">SHOULD</span> terminate a session when the
        certificate received in the handshake expires.<a href="#section-7.2-1" class="pilcrow">¶</a></p>
</section>
<section id="section-7.3">
        <h3 id="name-algorithms-and-cryptographi">
<a href="#section-7.3" class="section-number selfRef">7.3. </a><a href="#name-algorithms-and-cryptographi" class="section-name selfRef">Algorithms and Cryptographic Strength</a>
        </h3>
<p id="section-7.3-1"> All ITS certificates use public-key cryptographic algorithms with
        an estimated strength on the order of 128 bits or more, specifically,
        Elliptic Curve Cryptography (ECC) based on curves with keys of length
        256 bits or longer. An implementation of the techniques specified in
        this document <span class="bcp14">SHOULD</span> require that if X.509 certificates
        are used by one of the parties to the session, those certificates are
        associated with cryptographic algorithms with (pre-quantum-computer)
        strength of at least 128 bits.<a href="#section-7.3-1" class="pilcrow">¶</a></p>
</section>
<div id="ITS-permissions">
<section id="section-7.4">
        <h3 id="name-interpreting-its-certificat">
<a href="#section-7.4" class="section-number selfRef">7.4. </a><a href="#name-interpreting-its-certificat" class="section-name selfRef">Interpreting ITS Certificate Permissions</a>
        </h3>
<p id="section-7.4-1"> ITS certificates in TLS express the certificate holders
        permissions using two fields: a PSID, also known as an ITS Application
        Identifier (ITS-AID), which identifies a broad set of application
        activities that provide a context for the certificate holder's
        permissions, and a Service Specific Permissions (SSP) field associated
        with that PSID, which identifies which specific application activities
        the certificate holder is entitled to carry out within the broad set
        of activities identified by that PSID.  For example, SAE <span>[<a href="#SAEJ29453" class="xref">SAEJ29453</a>]</span> uses PSID 0204099 to indicate
        activities around reporting weather and managing weather response
        activities, and an SSP that states whether the certificate holder is a
        Weather Data Management System (WDMS, i.e., a central road manager),
        an ordinary vehicle, or a vehicle belonging to a managed road
        maintenance fleet. For more information about PSIDs, see <span>[<a href="#IEEE1609.12" class="xref">IEEE1609.12</a>]</span>, and for more information about
        the development of SSPs, see <span>[<a href="#SAEJ29455" class="xref">SAEJ29455</a>]</span>.<a href="#section-7.4-1" class="pilcrow">¶</a></p>
</section>
</div>
<section id="section-7.5">
        <h3 id="name-psid-and-pdufunctionaltype-">
<a href="#section-7.5" class="section-number selfRef">7.5. </a><a href="#name-psid-and-pdufunctionaltype-" class="section-name selfRef">Psid and Pdufunctionaltype in CertificateVerify</a>
        </h3>
<p id="section-7.5-1"> The CertificateVerify message for TLS 1.3 is an Ieee1609Dot2Data
        of type signed, where the signature contained in this Ieee1609Dot2Data
 was generated using an ITS certificate. This certificate may
        include multiple PSIDs. When a CertificateVerify message of this form
        is used, the HeaderInfo within the Ieee1609Dot2Data
        <span class="bcp14">MUST</span> have the pduFunctionalType field present and set
        to tlsHandshake. The background to this requirement is as follows: an
        ITS certificate may (depending on the definition of the application
        associated with its PSID(s)) be used to directly sign messages or to
        sign TLS CertificateVerify messages, or both. To prevent the
        possibility that a signature generated in one context could be
        replayed in a different context, i.e., that a message signature could
        be replayed as a CertificateVerify, or vice versa, the
        pduFunctionalType field provides a statement of intent by the signer
        as to the intended use of the signed message. If the pduFunctionalType
        field is absent, the message is a directly signed message for the
        application and <span class="bcp14">MUST NOT</span> be interpreted as a
        CertificateVerify.<a href="#section-7.5-1" class="pilcrow">¶</a></p>
<p id="section-7.5-2"> Note that each PSID is owned by an owning organization that has
        sole rights to define activities associated with that PSID. If an
        application specifier wishes to expand activities associated with an
        existing PSID (for example, to include activities over a secure
        session such as specified in this document), that application
        specifier must negotiate with the PSID owner to have that
        functionality added to the official specification of activities
        associated with that PSID.<a href="#section-7.5-2" class="pilcrow">¶</a></p>
</section>
</section>
<section id="section-8">
      <h2 id="name-privacy-considerations">
<a href="#section-8" class="section-number selfRef">8. </a><a href="#name-privacy-considerations" class="section-name selfRef">Privacy Considerations</a>
      </h2>
<p id="section-8-1">For privacy considerations in a vehicular environment, the ITS
      certificate is used for many reasons:<a href="#section-8-1" class="pilcrow">¶</a></p>
<ul class="normal">
<li class="normal" id="section-8-2.1">In order to address the risk of a personal data leakage, messages
        exchanged for vehicle-to-vehicle (V2V) communications are signed using ITS pseudonym
        certificates.<a href="#section-8-2.1" class="pilcrow">¶</a>
</li>
        <li class="normal" id="section-8-2.2">The purpose of these certificates is to provide privacy and
        minimize the exchange of private data.<a href="#section-8-2.2" class="pilcrow">¶</a>
</li>
      </ul>
</section>
<div id="IANA">
<section id="section-9">
      <h2 id="name-iana-considerations">
<a href="#section-9" class="section-number selfRef">9. </a><a href="#name-iana-considerations" class="section-name selfRef">IANA Considerations</a>
      </h2>
<p id="section-9-1">IANA maintains the "Transport Layer Security (TLS) Extensions"
      registry with a subregistry called "TLS Certificate Types".<a href="#section-9-1" class="pilcrow">¶</a></p>
<p id="section-9-2">Value 3 was previously assigned for "1609Dot2" and included a 
  reference to draft-tls-certieee1609.  IANA has updated this
  entry to reference this RFC.<a href="#section-9-2" class="pilcrow">¶</a></p>
</section>
</div>
<section id="section-10">
      <h2 id="name-normative-references">
<a href="#section-10" class="section-number selfRef">10. </a><a href="#name-normative-references" class="section-name selfRef">Normative References</a>
      </h2>
<dl class="references">
<dt id="IEEE1609.12">[IEEE1609.12]</dt>
      <dd>
<span class="refAuthor">IEEE</span>, <span class="refTitle">"IEEE Standard for Wireless Access in Vehicular Environments (WAVE) - Identifier Allocations"</span>, <span class="refContent">IEEE 1609.12-2016</span>, <time datetime="2016-12" class="refDate">December 2016</time>. </dd>
<dd class="break"></dd>
<dt id="IEEE1609.2">[IEEE1609.2]</dt>
      <dd>
<span class="refAuthor">IEEE</span>, <span class="refTitle">"IEEE Standard for Wireless Access in Vehicular Environments -- Security Services for Applications and Management Messages"</span>, <span class="refContent">IEEE Standard 1609.2-2016</span>, <span class="seriesInfo">DOI 10.1109/IEEESTD.2016.7426684</span>, <time datetime="2016-03" class="refDate">March 2016</time>, <span>&lt;<a href="https://doi.org/10.1109/IEEESTD.2016.7426684">https://doi.org/10.1109/IEEESTD.2016.7426684</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="IEEE1609.2b">[IEEE1609.2b]</dt>
      <dd>
<span class="refAuthor">IEEE</span>, <span class="refTitle">"IEEE Standard for Wireless Access in Vehicular Environments--Security Services for Applications and Management Messages - Amendment 2--PDU Functional Types and Encryption Key Management"</span>, <span class="refContent">IEEE 1609.2b-2019</span>, <time datetime="2019-06" class="refDate">June 2019</time>. </dd>
<dd class="break"></dd>
<dt id="ISO21177">[ISO21177]</dt>
      <dd>
<span class="refAuthor">ISO</span>, <span class="refTitle">"Intelligent transport systems - ITS station security services for secure session establishment and authentication between trusted devices"</span>, <span class="refContent">ISO/TS 21177:2019</span>, <time datetime="2019-08" class="refDate">August 2019</time>. </dd>
<dd class="break"></dd>
<dt id="ITU-TX.696">[ITU-TX.696]</dt>
      <dd>
<span class="refAuthor">ITU-T</span>, <span class="refTitle">"Information technology - ASN.1 encoding rules: Specification of Octet Encoding Rules (OER)"</span>, <span class="refContent">Recommendation ITU-T X.696</span>, <time datetime="2015-08" class="refDate">August 2015</time>. </dd>
<dd class="break"></dd>
<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="RFC7250">[RFC7250]</dt>
      <dd>
<span class="refAuthor">Wouters, P., Ed.</span><span class="refAuthor">, Tschofenig, H., Ed.</span><span class="refAuthor">, Gilmore, J.</span><span class="refAuthor">, Weiler, S.</span><span class="refAuthor">, and T. Kivinen</span>, <span class="refTitle">"Using Raw Public Keys in Transport Layer Security (TLS) and Datagram Transport Layer Security (DTLS)"</span>, <span class="seriesInfo">RFC 7250</span>, <span class="seriesInfo">DOI 10.17487/RFC7250</span>, <time datetime="2014-06" class="refDate">June 2014</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc7250">https://www.rfc-editor.org/info/rfc7250</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="RFC8446">[RFC8446]</dt>
      <dd>
<span class="refAuthor">Rescorla, E.</span>, <span class="refTitle">"The Transport Layer Security (TLS) Protocol Version 1.3"</span>, <span class="seriesInfo">RFC 8446</span>, <span class="seriesInfo">DOI 10.17487/RFC8446</span>, <time datetime="2018-08" class="refDate">August 2018</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc8446">https://www.rfc-editor.org/info/rfc8446</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="SAEJ29453">[SAEJ29453]</dt>
      <dd>
<span class="refAuthor">SAE</span>, <span class="refTitle">"Requirements for V2I Weather Applications"</span>, <span class="refContent">J2945/3</span>, <time datetime="2017-06" class="refDate">June 2017</time>. </dd>
<dd class="break"></dd>
<dt id="SAEJ29455">[SAEJ29455]</dt>
      <dd>
<span class="refAuthor">SAE</span>, <span class="refTitle">"Service Specific Permissions and Security Guidelines for Connected Vehicle Applications"</span>, <span class="refContent">J2945/5_202002</span>, <time datetime="2020-02" class="refDate">February 2020</time>. </dd>
<dd class="break"></dd>
<dt id="TS102941">[TS102941]</dt>
      <dd>
<span class="refAuthor">ETSI</span>, <span class="refTitle">"Intelligent Transport Systems (ITS); Security; Trust and Privacy Management"</span>, <span class="refContent">ETSI TS 102 941</span>, <time datetime="2018" class="refDate">2018</time>. </dd>
<dd class="break"></dd>
<dt id="TS103097">[TS103097]</dt>
    <dd>
<span class="refAuthor">ETSI</span>, <span class="refTitle">"Intelligent Transport Systems (ITS); Security; Security header and certificate formats"</span>, <span class="refContent">ETSI TS 103 097</span>, <span>2017</span>. </dd>
<dd class="break"></dd>
</dl>
</section>
<div id="ack">
<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">The authors wish to thank <span class="contact-name">Adrian Farrel</span>,
      <span class="contact-name">Eric Rescola</span>, <span class="contact-name">Russ Housley</span>,
      <span class="contact-name">Ilari Liusvaara</span>, and <span class="contact-name">Benjamin       Kaduk</span> for their feedback and suggestions on improving this document.
      Thanks are due to <span class="contact-name">Sean Turner</span> for his valuable and detailed
      comments. Special thanks to <span class="contact-name">Panos Kampanakis</span>,
      <span class="contact-name">Jasja Tijink</span>, and <span class="contact-name">Bill       Lattin</span> for their guidance and support of the document.<a href="#section-appendix.a-1" class="pilcrow">¶</a></p>
</section>
</div>
<div id="authors-addresses">
<section id="section-appendix.b">
      <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">Mounira Msahli (<span class="role">editor</span>)</span></div>
<div dir="auto" class="left"><span class="org">Telecom Paris</span></div>
<div dir="auto" class="left"><span class="country-name">France</span></div>
<div class="email">
<span>Email:</span>
<a href="mailto:mounira.msahli@telecom-paris.fr" class="email">mounira.msahli@telecom-paris.fr</a>
</div>
</address>
<address class="vcard">
        <div dir="auto" class="left"><span class="fn nameRole">Nancy Cam-Winget (<span class="role">editor</span>)</span></div>
<div dir="auto" class="left"><span class="org">Cisco</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:ncamwing@cisco.com" class="email">ncamwing@cisco.com</a>
</div>
</address>
<address class="vcard">
        <div dir="auto" class="left"><span class="fn nameRole">William Whyte (<span class="role">editor</span>)</span></div>
<div dir="auto" class="left"><span class="org">Qualcomm</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:wwhyte@qti.qualcomm.com" class="email">wwhyte@qti.qualcomm.com</a>
</div>
</address>
<address class="vcard">
        <div dir="auto" class="left"><span class="fn nameRole">Ahmed Serhrouchni</span></div>
<div dir="auto" class="left"><span class="org">Telecom Paris</span></div>
<div dir="auto" class="left"><span class="country-name">France</span></div>
<div class="email">
<span>Email:</span>
<a href="mailto:ahmed.serhrouchni@telecom-paris.fr" class="email">ahmed.serhrouchni@telecom-paris.fr</a>
</div>
</address>
<address class="vcard">
        <div dir="auto" class="left"><span class="fn nameRole">Houda Labiod</span></div>
<div dir="auto" class="left"><span class="org">Telecom Paris</span></div>
<div dir="auto" class="left"><span class="country-name">France</span></div>
<div class="email">
<span>Email:</span>
<a href="mailto:houda.labiod@telecom-paris.fr" class="email">houda.labiod@telecom-paris.fr</a>
</div>
</address>
</section>
</div>
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