Re: SYN_REPLY

William Chan (陈智昌) <willchan@chromium.org> Wed, 27 February 2013 20:00 UTC

Return-Path: <ietf-http-wg-request@listhub.w3.org>
X-Original-To: ietfarch-httpbisa-archive-bis2Juki@ietfa.amsl.com
Delivered-To: ietfarch-httpbisa-archive-bis2Juki@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 5B13521F8B71 for <ietfarch-httpbisa-archive-bis2Juki@ietfa.amsl.com>; Wed, 27 Feb 2013 12:00:28 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -9.464
X-Spam-Level:
X-Spam-Status: No, score=-9.464 tagged_above=-999 required=5 tests=[AWL=0.212, BAYES_00=-2.599, FM_FORGED_GMAIL=0.622, HTML_MESSAGE=0.001, MIME_8BIT_HEADER=0.3, RCVD_IN_DNSWL_HI=-8]
Received: from mail.ietf.org ([64.170.98.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id kyVG136-FrUd for <ietfarch-httpbisa-archive-bis2Juki@ietfa.amsl.com>; Wed, 27 Feb 2013 12:00:23 -0800 (PST)
Received: from frink.w3.org (frink.w3.org [128.30.52.56]) by ietfa.amsl.com (Postfix) with ESMTP id 2F80B21F8B7D for <httpbisa-archive-bis2Juki@lists.ietf.org>; Wed, 27 Feb 2013 12:00:22 -0800 (PST)
Received: from lists by frink.w3.org with local (Exim 4.72) (envelope-from <ietf-http-wg-request@listhub.w3.org>) id 1UAnA3-0006zg-9b for ietf-http-wg-dist@listhub.w3.org; Wed, 27 Feb 2013 19:59:31 +0000
Resent-Date: Wed, 27 Feb 2013 19:59:31 +0000
Resent-Message-Id: <E1UAnA3-0006zg-9b@frink.w3.org>
Received: from lisa.w3.org ([128.30.52.41]) by frink.w3.org with esmtp (Exim 4.72) (envelope-from <willchan@google.com>) id 1UAn9t-0006wh-6m for ietf-http-wg@listhub.w3.org; Wed, 27 Feb 2013 19:59:21 +0000
Received: from mail-qc0-f172.google.com ([209.85.216.172]) by lisa.w3.org with esmtps (TLS1.0:RSA_ARCFOUR_SHA1:16) (Exim 4.72) (envelope-from <willchan@google.com>) id 1UAn9s-0003Es-IX for ietf-http-wg@w3.org; Wed, 27 Feb 2013 19:59:21 +0000
Received: by mail-qc0-f172.google.com with SMTP id b25so77442qca.3 for <ietf-http-wg@w3.org>; Wed, 27 Feb 2013 11:58:54 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=mime-version:x-received:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type; bh=VgbRe+iS7hPIyA+17FzksJhBSg8usYgEoFVV7vCy4M4=; b=lDUtf1R7EfAeQId8i7anQ60kMll5Ut+ZuJPj+z/j0EgT+Um94Mt1IqGcgTfo72UJnj B0ef7vOVLUt2Qfw3E5l+cVWl52+bGJF/j9KDPPX/KbdG5hRZ7PO13Eo3HY6dFjwJ4Vwq gkx5HnV3bRYPxH/GTY57R5o4RZZl+ew58leRxnCO5FAq2IvOAYrDn2aM62PWeFI6X6EE tmF1Nhv8QFSkQNf9lrUlUKUAOqkrCnM5snH37BfEeL0374Tx5z73QPmPRykCd12Qtm9U B3n/MQvYwOyD4DP8SVqiuIxek+nfE3lNvRz3acWqw39JQXOZCUuynbRTBDRL2L+tLhvI rzFw==
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=mime-version:x-received:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type; bh=VgbRe+iS7hPIyA+17FzksJhBSg8usYgEoFVV7vCy4M4=; b=NluZPKObyyfSXm4c8QbgSAnKyvmghxM6pJg4a+cGuWfvmKLOeKaOoHHUt00DoPAFsd wpXfjYmPEYi4sDx6qcgKDAXIDoAo664u5YW8o7JHfL+89IlaxY92D/p5JSas2LlJh4Tp fz62rOvQmHWn4oaqP64pfRQMHArhxlb5TsgGg=
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=mime-version:x-received:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :x-gm-message-state; bh=VgbRe+iS7hPIyA+17FzksJhBSg8usYgEoFVV7vCy4M4=; b=BDQnXaKKMzWtUCgbqIFwRscDVpcZaMM3Rf+ToJhJeWocGdKUWn9E37mang+n9lSyC1 o8/Ta1wijI6WZhqHnJw4HtRsn522HV7Srr6pF4yELWoe3Xnm43W6VL4QMovCejs+Rb2+ kuz5Pt8L7SpwuuAZ93ZphjV/1TGEvQjbXgQ8P8xc59fJtZ/tE6zZbTDlKsZV0v/zVhzC wZwrdm3RFOKgcRf6WRJTn+NVIQ673RG5Jg3X79d520yPdniNepcEdjbp5PB18tGEle8N oa39jq/ki2CIv4c+YlciawAxgqLeM40es7nN8DuvUwx4mwlF7Sr+qmuiywc/BgIuGq5p hPlg==
MIME-Version: 1.0
X-Received: by 10.224.180.212 with SMTP id bv20mr9881745qab.6.1361995134608; Wed, 27 Feb 2013 11:58:54 -0800 (PST)
Sender: willchan@google.com
Received: by 10.229.135.210 with HTTP; Wed, 27 Feb 2013 11:58:54 -0800 (PST)
In-Reply-To: <CABkgnnWALH=TpYYJAYKwQgNXn7J3CdE=a_9jes0cNqSKKQAwiQ@mail.gmail.com>
References: <CABkgnnU5he8x=v+UvV8Oe7mS-3FnMtLmjaz_xk+Ns84LzCpvwQ@mail.gmail.com> <CAP+FsNdkoFXwWoxGAVGh1Sy6+3EDrzOo-hgP6=9+0PnYaxzXbQ@mail.gmail.com> <CAP+FsNdYVkjBVRnJAdsHcjHJg_dw3f7T81Br=ioDNcXUG3V0=w@mail.gmail.com> <CABkgnnUc4C2wTKX9naV9Ver7H9gTnqP84n_8+3QKDRXFyP04jA@mail.gmail.com> <CAP+FsNffguLnO--8SoGo2ceYTJpWut+6PuGN=p4rL84d6TvBrw@mail.gmail.com> <CABkgnnUcOFY=FtESWyhmayUvFvz===w=_KndNjM_diLkcSOQSw@mail.gmail.com> <CAP+FsNd_3eqoOgOgeXe629dYSaiEosh1m5AOaO_MyKGK=BQmpw@mail.gmail.com> <CAP+FsNcRYa55pe-xAwooZYTPjkcN7h3MgCr1Gy7gWYf6EQSydA@mail.gmail.com> <CAA4WUYj7SJ+QtzANL+hwEfVmO3jZvPgQjTbxs4es0ecnVG3-fg@mail.gmail.com> <CAP+FsNefW3K=H6-Ax9ip4R=VTrTECQ+943BPUBQJ=cV2jo_UMQ@mail.gmail.com> <CAA4WUYiWy1UGUcUVvQMN_W5pTxXEmBSUCFxAaRmzH1U0tBK71A@mail.gmail.com> <CABkgnnWSqRYAPz3mb1gS3_+O60okZK5NTnzHQC2-NBizsYZgbg@mail.gmail.com> <CAA4WUYh13LOL-NRgeyR3EFf+5p1czs8SEUrMdReOr3=1v8Vb1g@mail.gmail.com> <512D7F92.6030501@treenet.co.nz> <CAA4WUYjmC2Wg3r7CiqSTJXoW6y_CYyRQB4u9dLzkQ4aCWnnL5A@mail.gmail.com> <CAP+FsNfA7+iun5pE_vTqN-ciaJ7kfj_PStdc6HJ1f-yGUR=kUA@mail.gmail.com> <CAA4WUYiaZ6ftTePFiMkJ5y4rBd2eXjnrzk1c24-VYqAEe0ystw@mail.gmail.com> <CAP+FsNdntyXmD71R76kXZFu0E--tv5zT2f5djL4YC6sRq6HdMQ@mail.gmail.com> <CABkgnnWjYgxbcnEo5SiU_0dN8uSt6SNpjzY0BVvooeHo18T7ng@mail.gmail.com> <CAP+FsNfp=wtRVR0dQVe_YcPp0yzQU545THv5byObRdsyOUwPSg@mail.gmail.com> <CABkgnnXzrmHKZjCvsCSB7FnPA_CLqEfO02iMjj2BDHuEDpt2Bg@mail.gmail.com> <CAP+FsNdeey2UK1KF-Ejy2SX_aznJi07q+=uPvYuT58wVEjmSNQ@mail.gmail.com> <CABkgnnW7n+c17mOVKNya5jVxW5A=8HPb_Ez=_JDQB8eWiNfdsQ@mail.gmail.com> <CAP+FsNc--=0Zg7Kg3hbOfTdYE+Af5G3wgd20CEY+QMTVMnW5XA@mail.gmail.com> <CABkgnnWALH=TpYYJAYKwQgNXn7J3CdE=a_9jes0cNqSKKQAwiQ@mail.gmail.com>
Date: Wed, 27 Feb 2013 11:58:54 -0800
X-Google-Sender-Auth: jPkYdr5RzK7O7Spyuu1nER4MSp0
Message-ID: <CAA4WUYjRbeGd-TDjB5mTseVXAHhVEWvY2rJgS5-SyHG-+=D_Gw@mail.gmail.com>
From: "William Chan (陈智昌)" <willchan@chromium.org>
To: Martin Thomson <martin.thomson@gmail.com>
Cc: Roberto Peon <grmocg@gmail.com>, Amos Jeffries <squid3@treenet.co.nz>, HTTP Working Group <ietf-http-wg@w3.org>
Content-Type: multipart/alternative; boundary="20cf303b40c32f49d704d6ba3406"
X-Gm-Message-State: ALoCoQkSi89BFfEbkXedgkzC3V420CvM+JOMgRWy5FyZers+oXoluOR24XYsz1fOtt8WRXfrqEffx3Q9/kXcRE5uzN2kCvkZQAB576XYCGFzcydoL+08rbejR5E15jUht4nM2R4IN0/V1PPUgrV8ZfSsk9Z6jXdFCJXIMJUiGwSPdSMMpzjWC1uD3WuDJ5gaol5Mlll89Vxk
Received-SPF: pass client-ip=209.85.216.172; envelope-from=willchan@google.com; helo=mail-qc0-f172.google.com
X-W3C-Hub-Spam-Status: No, score=-3.9
X-W3C-Hub-Spam-Report: AWL=-2.349, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_LOW=-0.7, RP_MATCHES_RCVD=-0.703, SPF_PASS=-0.001
X-W3C-Scan-Sig: lisa.w3.org 1UAn9s-0003Es-IX cde183dd01855ab86b4fa07679436ff0
X-Original-To: ietf-http-wg@w3.org
Subject: Re: SYN_REPLY
Archived-At: <http://www.w3.org/mid/CAA4WUYjRbeGd-TDjB5mTseVXAHhVEWvY2rJgS5-SyHG-+=D_Gw@mail.gmail.com>
Resent-From: ietf-http-wg@w3.org
X-Mailing-List: <ietf-http-wg@w3.org> archive/latest/16898
X-Loop: ietf-http-wg@w3.org
Resent-Sender: ietf-http-wg-request@w3.org
Precedence: list
List-Id: <ietf-http-wg.w3.org>
List-Help: <http://www.w3.org/Mail/>
List-Post: <mailto:ietf-http-wg@w3.org>
List-Unsubscribe: <mailto:ietf-http-wg-request@w3.org?subject=unsubscribe>

I'm fine with this but there are details that need to be covered in the
spec. When a stream starts, the client MUST use the HEADERS+PRIORITY frame.
Otherwise, we need to spec out what happens when you have some streams with
unspecified priority and some streams with specified priority. I'd rather
just mandate we always include the priority. For clients which don't care
about priority, always pick the same arbitrary value.

PS: I raised a minor point earlier about possibly allowing bidirectional
server initiated streams. I don't feel strongly about it, and if an actual
use case arises, I'm happy to re-raise later.


On Wed, Feb 27, 2013 at 11:51 AM, Martin Thomson
<martin.thomson@gmail.com>wrote:

> OK, here's where I think we're at, in concrete terms:
>
> We have a HEADERS frame.
> We have a HEADERS+PRIORITY frame that includes an extra 4 bytes up front.
>
> Either can be sent in all the normal places that you would expect to
> see HEADERS, SYN_STREAM or SYN_REPLY.  Most importantly, when a stream
> starts.
>
> Pushed streams are unidirectional by virtue of being initiated by the
> server, not by explicit indication.  The server does not expect data
> frames from the client and MAY discard them.
>