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<!DOCTYPE html SYSTEM "about:legacy-compat"> <html lang="en"><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"><title>RFC 9220 - Bootstrapping WebSockets with HTTP/3</title><script> function getMeta(rfcno, container) { var xhr = new XMLHttpRequest(); xhr.open("GET", "https://www.rfc-editor.org/rfc/rfc" + rfcno + ".json", true); xhr.onload = function (e) { if (xhr.readyState === 4) { if (xhr.status === 200) { var data = JSON.parse(xhr.response); var cont = document.getElementById(container); // empty the container while (cont.firstChild) { cont.removeChild(myNode.firstChild); } var c = data.status; if (c) { var bld = newElementWithText("b", c); cont.appendChild(bld); } else { cont.appendChild(newElementWithText("i", "(document status unknown)")); } c = data.updated_by; if (c && c.length > 0 && c[0] !== null && c[0].length > 0) { cont.appendChild(newElement("br")); cont.appendChild(newText("Updated by: ")); appendRfcLinks(cont, c); } c = data.obsoleted_by; if (c && c.length > 0 && c[0] !== null && c[0].length > 0) { cont.appendChild(newElement("br")); cont.appendChild(newText("Obsoleted by: ")); appendRfcLinks(cont, c); } c = data.errata_url; if (c) { cont.appendChild(newElement("br")); var link = newElementWithText("a", "errata"); link.setAttribute("href", c); var errata = newElementWithText("i", "This document has "); errata.appendChild(link); errata.appendChild(newText(".")); cont.appendChild(errata); } cont.style.display = "block"; } else { console.error(xhr.statusText); } } }; xhr.onerror = function (e) { console.error(xhr.status + " " + xhr.statusText); }; xhr.send(null); } function appendRfcLinks(parent, updates) { var template = "https://www.rfc-editor.org/rfc/rfc{rfc}.html"; for (var i = 0; i < updates.length; i++) { var rfc = updates[i].trim().toLowerCase(); if (rfc.substring(0, 3) == "rfc") { var no = parseInt(rfc.substring(3), 10); var link = newElement("a"); link.setAttribute("href", template.replace("{rfc}", no)); link.appendChild(newText(no)); parent.appendChild(link); } else { parent.appendChild(newText(rfc)); } if (i != updates.length - 1) { parent.appendChild(newText(", ")); } } } // DOM helpers function newElement(name) { return document.createElement(name); } function newElementWithText(name, txt) { var e = document.createElement(name); e.appendChild(newText(txt)); return e; } function newText(text) { return document.createTextNode(text); } </script><script> function anchorRewrite() { map = { }; if (window.location.hash.length >= 1) { var fragid = window.location.hash.substr(1); if (fragid) { if (! 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This document describes how the mechanism is adapted for HTTP/3."><meta name="dcterms.isPartOf" content="urn:issn:2070-1721"><meta name="description" content="The mechanism for running the WebSocket Protocol over a single stream of an HTTP/2 connection is equally applicable to HTTP/3, but the HTTP-version-specific details need to be specified. 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Hamilton</td></tr><tr><td class="text-left">Request for Comments: 9220</td><td class="text-right">Google</td></tr><tr><td class="text-left">Category: Standards Track</td><td class="text-right">June 2022</td></tr><tr><td class="text-left">ISSN: 2070-1721</td><td class="text-right"></td></tr></tbody></table><div id="rfc.title"><h1>Bootstrapping WebSockets with HTTP/3</h1></div></header><hr><h2 id="rfc.abstract"><a href="#rfc.abstract">Abstract</a></h2><div class="lead"><div id="rfc.abstract.p.1"><p>The mechanism for running the WebSocket Protocol over a single stream of an HTTP/2 connection is equally applicable to HTTP/3, but the HTTP-version-specific details need to be specified. This document describes how the mechanism is adapted for HTTP/3.</p></div></div><aside id="rfc.meta" class="alert alert-info"></aside><section id="rfc.status"><h2><a href="#rfc.status">Status of This Memo</a></h2><div id="rfc.boilerplate.1.p.1"><p>This is an Internet Standards Track document.</p></div><div id="rfc.boilerplate.1.p.2"><p>This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in <a href="https://www.rfc-editor.org/rfc/rfc7841.html#section-2">Section 2 of RFC 7841</a>.</p></div><div id="rfc.boilerplate.1.p.3"><p>Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at <a href="https://www.rfc-editor.org/info/rfc9220">https://www.rfc-editor.org/info/rfc9220</a>.</p></div></section><section id="rfc.copyrightnotice"><h2><a href="#rfc.copyrightnotice">Copyright Notice</a></h2><div id="rfc.boilerplate.2.p.1"><p>Copyright (c) 2022 IETF Trust and the persons identified as the document authors. All rights reserved.</p></div><div id="rfc.boilerplate.2.p.2"><p>This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (<a href="https://trustee.ietf.org/license-info">https://trustee.ietf.org/license-info</a>) 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 Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License.</p></div></section><div class="toc d-lg-none"><ul><li><a href="#rfc.section.1">1.</a>   <a href="#introduction">Introduction</a></li><li><a href="#rfc.section.2">2.</a>   <a href="#conventions-and-definitions">Conventions and Definitions</a></li><li><a href="#rfc.section.3">3.</a>   <a href="#websockets-upgrade-over-http3">WebSockets Upgrade over HTTP/3</a></li><li><a href="#rfc.section.4">4.</a>   <a href="#security-considerations">Security Considerations</a></li><li><a href="#rfc.section.5">5.</a>   <a href="#iana-considerations">IANA Considerations</a></li><li><a href="#rfc.section.6">6.</a>   <a href="#rfc.references">Normative References</a></li><li><a href="#acknowledgments">Acknowledgments</a></li><li><a href="#rfc.authors">Author's Address</a></li></ul></div><hr class="hidden-print"><section id="introduction"><h2 id="rfc.section.1" class="np"><a href="#rfc.section.1">1.</a> <a href="#introduction">Introduction</a></h2><div id="rfc.section.1.p.1"><p>"<a href="#RFC8441"><cite title="Bootstrapping WebSockets with HTTP/2">Bootstrapping WebSockets with HTTP/2</cite></a>" <a href="#RFC8441"><cite title="Bootstrapping WebSockets with HTTP/2">[RFC8441]</cite></a> defines an extension to HTTP/2 <a href="#HTTP2"><cite title="HTTP/2">[HTTP/2]</cite></a> that is also useful in HTTP/3 <a href="#HTTP3"><cite title="HTTP/3">[HTTP/3]</cite></a>. This extension makes use of an HTTP/2 setting. <a href="https://www.rfc-editor.org/rfc/rfc9114.html#appendix-A.3">Appendix A.3</a> of <a href="#HTTP3"><cite title="HTTP/3">[HTTP/3]</cite></a> gives some guidance on what changes (if any) are appropriate when porting settings from HTTP/2 to HTTP/3.</p></div></section><hr class="hidden-print"><section id="conventions-and-definitions"><h2 id="rfc.section.2" class="np"><a href="#rfc.section.2">2.</a> <a href="#conventions-and-definitions">Conventions and Definitions</a></h2><div id="rfc.section.2.p.1"><p>The key words "<em class="bcp14">MUST</em>", "<em class="bcp14">MUST NOT</em>", "<em class="bcp14">REQUIRED</em>", "<em class="bcp14">SHALL</em>", "<em class="bcp14">SHALL NOT</em>", "<em class="bcp14">SHOULD</em>", "<em class="bcp14">SHOULD NOT</em>", "<em class="bcp14">RECOMMENDED</em>", "<em class="bcp14">NOT RECOMMENDED</em>", "<em class="bcp14">MAY</em>", and "<em class="bcp14">OPTIONAL</em>" in this document are to be interpreted as described in <span class="nobr">BCP 14</span> <a href="#RFC2119"><cite title="Key words for use in RFCs to Indicate Requirement Levels">[RFC2119]</cite></a> <a href="#RFC8174"><cite title="Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words">[RFC8174]</cite></a> when, and only when, they appear in all capitals, as shown here.</p></div></section><hr class="hidden-print"><section id="websockets-upgrade-over-http3"><h2 id="rfc.section.3" class="np"><a href="#rfc.section.3">3.</a> <a href="#websockets-upgrade-over-http3">WebSockets Upgrade over HTTP/3</a></h2><div id="rfc.section.3.p.1"><p><a href="#RFC8441"><cite title="Bootstrapping WebSockets with HTTP/2">[RFC8441]</cite></a> defines a mechanism for running the WebSocket Protocol <a href="#RFC6455"><cite title="The WebSocket Protocol">[RFC6455]</cite></a> over a single stream of an HTTP/2 connection. It defines an Extended CONNECT method that specifies a new ":protocol" pseudo-header field and new semantics for the ":path" and ":authority" pseudo-header fields. It also defines a new HTTP/2 setting sent by a server to allow the client to use Extended CONNECT.</p></div><div id="rfc.section.3.p.2"><p>The semantics of the pseudo-header fields and setting are identical to those in HTTP/2 as defined in <a href="#RFC8441"><cite title="Bootstrapping WebSockets with HTTP/2">[RFC8441]</cite></a>. <a href="https://www.rfc-editor.org/rfc/rfc9114.html#appendix-A.3">Appendix A.3</a> of <a href="#HTTP3"><cite title="HTTP/3">[HTTP/3]</cite></a> requires that HTTP/3 settings be registered separately for HTTP/3. The SETTINGS_ENABLE_CONNECT_PROTOCOL value is 0x08 (decimal 8), as in HTTP/2.</p></div><div id="rfc.section.3.p.3"><p>If a server advertises support for Extended CONNECT but receives an Extended CONNECT request with a ":protocol" value that is unknown or is not supported, the server <em class="bcp14">SHOULD</em> respond to the request with a 501 (Not Implemented) status code (<a href="https://www.rfc-editor.org/rfc/rfc9110.html#section-15.6.2">Section 15.6.2</a> of <a href="#HTTP"><cite title="HTTP Semantics">[HTTP]</cite></a>). A server <em class="bcp14">MAY</em> provide more information via a "problem details" response <a href="#RFC7807"><cite title="Problem Details for HTTP APIs">[RFC7807]</cite></a>.</p></div><div id="rfc.section.3.p.4"><p>The HTTP/3 stream closure is also analogous to the TCP connection closure of <a href="#RFC6455"><cite title="The WebSocket Protocol">[RFC6455]</cite></a>. Orderly TCP-level closures are represented as a FIN bit on the stream (<a href="https://www.rfc-editor.org/rfc/rfc9114.html#section-4.4">Section 4.4</a> of <a href="#HTTP3"><cite title="HTTP/3">[HTTP/3]</cite></a>). RST exceptions are represented with a stream error (<a href="https://www.rfc-editor.org/rfc/rfc9114.html#section-8">Section 8</a> of <a href="#HTTP3"><cite title="HTTP/3">[HTTP/3]</cite></a>) of type H3_REQUEST_CANCELLED (<a href="https://www.rfc-editor.org/rfc/rfc9114.html#section-8.1">Section 8.1</a> of <a href="#HTTP3"><cite title="HTTP/3">[HTTP/3]</cite></a>).</p></div></section><hr class="hidden-print"><section id="security-considerations"><h2 id="rfc.section.4" class="np"><a href="#rfc.section.4">4.</a> <a href="#security-considerations">Security Considerations</a></h2><div id="rfc.section.4.p.1"><p>This document introduces no new security considerations beyond those discussed in <a href="#RFC8441"><cite title="Bootstrapping WebSockets with HTTP/2">[RFC8441]</cite></a>.</p></div></section><hr class="hidden-print"><section id="iana-considerations"><h2 id="rfc.section.5" class="np"><a href="#rfc.section.5">5.</a> <a href="#iana-considerations">IANA Considerations</a></h2><div id="rfc.section.5.p.1"><p>This document registers a new setting in the "HTTP/3 Settings" registry (<a href="https://www.rfc-editor.org/rfc/rfc9114.html#section-11.2.2">Section 11.2.2</a> of <a href="#HTTP3"><cite title="HTTP/3">[HTTP/3]</cite></a>).</p></div><div id="rfc.section.5.p.2"><dl class="compact"><dt>Value:</dt><dd style="margin-left: 1.5em"><div>0x08</div></dd><dt>Setting Name:</dt><dd style="margin-left: 1.5em"><div>SETTINGS_ENABLE_CONNECT_PROTOCOL</div></dd><dt>Default:</dt><dd style="margin-left: 1.5em"><div>0</div></dd><dt>Status:</dt><dd style="margin-left: 1.5em"><div>permanent</div></dd><dt>Specification:</dt><dd style="margin-left: 1.5em"><div>This document</div></dd><dt>Change Controller:</dt><dd style="margin-left: 1.5em"><div>IETF</div></dd><dt>Contact:</dt><dd style="margin-left: 1.5em"><div>HTTP Working Group (ietf-http-wg@w3.org)</div></dd></dl></div></section><section class="np"><div id="rfc.references"><h2 id="rfc.section.6"><a href="#rfc.section.6">6.</a> Normative References</h2><dl class="dl-horizontal"><dt id="HTTP">[<a href="#HTTP" class="smpl">HTTP</a>]</dt><dd>Fielding, R., Ed., Nottingham, M., Ed., and J. Reschke, Ed., “<a href="https://www.rfc-editor.org/rfc/rfc9110.html">HTTP Semantics</a>”, <a href="https://www.rfc-editor.org/info/std97">STD 97</a>, RFC 9110, <a href="https://dx.doi.org/10.17487/RFC9110">DOI 10.17487/RFC9110</a>, June 2022, <<a href="https://www.rfc-editor.org/info/rfc9110">https://www.rfc-editor.org/info/rfc9110</a>>.</dd><dt id="HTTP2">[<a href="#HTTP2" class="smpl">HTTP/2</a>]</dt><dd>Thomson, M., Ed. and C. Benfield, Ed., “<a href="https://www.rfc-editor.org/rfc/rfc9113.html">HTTP/2</a>”, RFC 9113, <a href="https://dx.doi.org/10.17487/RFC9113">DOI 10.17487/RFC9113</a>, June 2022, <<a href="https://www.rfc-editor.org/info/rfc9113">https://www.rfc-editor.org/info/rfc9113</a>>.</dd><dt id="HTTP3">[<a href="#HTTP3" class="smpl">HTTP/3</a>]</dt><dd>Bishop, M., Ed., “<a href="https://www.rfc-editor.org/rfc/rfc9114.html">HTTP/3</a>”, RFC 9114, <a href="https://dx.doi.org/10.17487/RFC9114">DOI 10.17487/RFC9114</a>, June 2022, <<a href="https://www.rfc-editor.org/info/rfc9114">https://www.rfc-editor.org/info/rfc9114</a>>.</dd><dt id="RFC2119">[<a href="#RFC2119" class="smpl">RFC2119</a>]</dt><dd>Bradner, S., “<a href="https://www.rfc-editor.org/rfc/rfc2119.html">Key words for use in RFCs to Indicate Requirement Levels</a>”, <a href="https://www.rfc-editor.org/info/bcp14">BCP 14</a>, RFC 2119, <a href="https://dx.doi.org/10.17487/RFC2119">DOI 10.17487/RFC2119</a>, March 1997, <<a href="https://www.rfc-editor.org/info/rfc2119">https://www.rfc-editor.org/info/rfc2119</a>>.</dd><dt id="RFC6455">[<a href="#RFC6455" class="smpl">RFC6455</a>]</dt><dd>Fette, I. and A. Melnikov, “<a href="https://www.rfc-editor.org/rfc/rfc6455.html">The WebSocket Protocol</a>”, RFC 6455, <a href="https://dx.doi.org/10.17487/RFC6455">DOI 10.17487/RFC6455</a>, December 2011, <<a href="https://www.rfc-editor.org/info/rfc6455">https://www.rfc-editor.org/info/rfc6455</a>>.</dd><dt id="RFC7807">[<a href="#RFC7807" class="smpl">RFC7807</a>]</dt><dd>Nottingham, M. and E. Wilde, “<a href="https://www.rfc-editor.org/rfc/rfc7807.html">Problem Details for HTTP APIs</a>”, RFC 7807, <a href="https://dx.doi.org/10.17487/RFC7807">DOI 10.17487/RFC7807</a>, March 2016, <<a href="https://www.rfc-editor.org/info/rfc7807">https://www.rfc-editor.org/info/rfc7807</a>>.</dd><dt id="RFC8174">[<a href="#RFC8174" class="smpl">RFC8174</a>]</dt><dd>Leiba, B., “<a href="https://www.rfc-editor.org/rfc/rfc8174.html">Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words</a>”, <a href="https://www.rfc-editor.org/info/bcp14">BCP 14</a>, RFC 8174, <a href="https://dx.doi.org/10.17487/RFC8174">DOI 10.17487/RFC8174</a>, May 2017, <<a href="https://www.rfc-editor.org/info/rfc8174">https://www.rfc-editor.org/info/rfc8174</a>>.</dd><dt id="RFC8441">[<a href="#RFC8441" class="smpl">RFC8441</a>]</dt><dd>McManus, P., “<a href="https://www.rfc-editor.org/rfc/rfc8441.html">Bootstrapping WebSockets with HTTP/2</a>”, RFC 8441, <a href="https://dx.doi.org/10.17487/RFC8441">DOI 10.17487/RFC8441</a>, September 2018, <<a href="https://www.rfc-editor.org/info/rfc8441">https://www.rfc-editor.org/info/rfc8441</a>>.</dd></dl></div></section><hr class="hidden-print"><section id="acknowledgments"><h2 id="rfc.section.unnumbered-4" class="np"><a href="#acknowledgments">Acknowledgments</a></h2><div id="rfc.section.unnumbered-4.p.1"><p>This document had reviews and input from many contributors in the IETF HTTP and QUIC Working Groups, with substantive input from David Schinazi, Martin Thomson, Lucas Pardue, Mike Bishop, Dragana Damjanovic, Mark Nottingham, and Julian Reschke.</p></div></section><hr class="hidden-print"><section id="rfc.authors" class="np"><h2><a href="#rfc.authors">Author's Address</a></h2><address><b>Ryan Hamilton</b><br>Google<br>EMail: <a href="mailto:rch@google.com">rch@google.com</a></address></section></div></div></div><script src="/assets/node_modules/jquery/dist/jquery.min.js"></script><script src="/assets/node_modules/bootstrap/dist/js/bootstrap.min.js"></script></body></html>