Date: Tue, 27 Dec 2016 14:26:08 -0800
From: Mike Bishop <notifications@github.com>
To: quicwg/base-drafts <base-drafts@noreply.github.com>
Message-ID: <quicwg/base-drafts/issues/104@github.com>
Subject: [quicwg/base-drafts] Priority in QUIC Transport (#104)
Mime-Version: 1.0
Content-Type: multipart/alternative;
 boundary="--==_mimepart_5862ea80bff00_33db3fb5df77d13c438775";
 charset=UTF-8
Content-Transfer-Encoding: 7bit
Precedence: list
Archived-At: <https://mailarchive.ietf.org/arch/msg/quic-issues/iDU9_xSowH-lnZiq5j_Z9Pq1juw>
Cc: Subscribed <subscribed@noreply.github.com>
Reply-To: quic@ietf.org

----==_mimepart_5862ea80bff00_33db3fb5df77d13c438775
Content-Type: text/plain;
 charset=UTF-8
Content-Transfer-Encoding: 7bit

The way HTTP/2 Priority is generally implemented is to keep a minimal amount in the TLS pipeline / TCP send buffer, retaining as much flexibility as possible to insert frames from high-priority streams ahead of those from lower-priority streams if they become available before the low-priority frames have been "committed".  Once data has been encrypted or sent to TCP, it must be sent even if higher-priority data has become available.

If the QUIC transport layer has no notion of priority, HTTP may have to do the same on each stream.  It might be preferable to provide the data for each stream into the transport as it becomes available, since the transport is already performing the framing functionality.

This need not be a wire format change (HTTP can continue to communicate priority at its layer), but should perhaps be noted as a useful property of an implementation and part of the defined interface with the application layer.

-- 
You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub:
https://github.com/quicwg/base-drafts/issues/104
----==_mimepart_5862ea80bff00_33db3fb5df77d13c438775
Content-Type: text/html;
 charset=UTF-8
Content-Transfer-Encoding: 7bit

<p>The way HTTP/2 Priority is generally implemented is to keep a minimal amount in the TLS pipeline / TCP send buffer, retaining as much flexibility as possible to insert frames from high-priority streams ahead of those from lower-priority streams if they become available before the low-priority frames have been "committed".  Once data has been encrypted or sent to TCP, it must be sent even if higher-priority data has become available.</p>
<p>If the QUIC transport layer has no notion of priority, HTTP may have to do the same on each stream.  It might be preferable to provide the data for each stream into the transport as it becomes available, since the transport is already performing the framing functionality.</p>
<p>This need not be a wire format change (HTTP can continue to communicate priority at its layer), but should perhaps be noted as a useful property of an implementation and part of the defined interface with the application layer.</p>

<p style="font-size:small;-webkit-text-size-adjust:none;color:#666;">&mdash;<br />You are receiving this because you are subscribed to this thread.<br />Reply to this email directly, <a href="https://github.com/quicwg/base-drafts/issues/104">view it on GitHub</a>, or <a href="https://github.com/notifications/unsubscribe-auth/AWbkq6dLmReAZN5WQcm5U9hVmoVjw5ddks5rMZCAgaJpZM4LWi4b">mute the thread</a>.<img alt="" height="1" src="https://github.com/notifications/beacon/AWbkq3Iu6Wb8OLgjqBwUD9Y7gFoeVxv7ks5rMZCAgaJpZM4LWi4b.gif" width="1" /></p>
<div itemscope itemtype="http://schema.org/EmailMessage">
<div itemprop="action" itemscope itemtype="http://schema.org/ViewAction">
  <link itemprop="url" href="https://github.com/quicwg/base-drafts/issues/104"></link>
  <meta itemprop="name" content="View Issue"></meta>
</div>
<meta itemprop="description" content="View this Issue on GitHub"></meta>
</div>

<script type="application/json" data-scope="inboxmarkup">{"api_version":"1.0","publisher":{"api_key":"05dde50f1d1a384dd78767c55493e4bb","name":"GitHub"},"entity":{"external_key":"github/quicwg/base-drafts","title":"quicwg/base-drafts","subtitle":"GitHub repository","main_image_url":"https://cloud.githubusercontent.com/assets/143418/17495839/a5054eac-5d88-11e6-95fc-7290892c7bb5.png","avatar_image_url":"https://cloud.githubusercontent.com/assets/143418/15842166/7c72db34-2c0b-11e6-9aed-b52498112777.png","action":{"name":"Open in GitHub","url":"https://github.com/quicwg/base-drafts"}},"updates":{"snippets":[{"icon":"DESCRIPTION","message":"Priority in QUIC Transport (#104)"}],"action":{"name":"View Issue","url":"https://github.com/quicwg/base-drafts/issues/104"}}}</script>
----==_mimepart_5862ea80bff00_33db3fb5df77d13c438775--