IETF Logo Mail Archive

Re: [hybi] permessage-deflate and missing asymmetric configurations

Tobias Oberstein <tobias.oberstein@tavendo.de> Sun, 13 October 2013 08:13 UTC

Return-Path: <tobias.oberstein@tavendo.de>
X-Original-To: hybi@ietfa.amsl.com
Delivered-To: hybi@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 2A95A11E8127 for <hybi@ietfa.amsl.com>; Sun, 13 Oct 2013 01:13:32 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.599
X-Spam-Level:
X-Spam-Status: No, score=-2.599 tagged_above=-999 required=5 tests=[AWL=0.000, BAYES_00=-2.599]
Received: from mail.ietf.org ([12.22.58.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id E6Mz-039ak1W for <hybi@ietfa.amsl.com>; Sun, 13 Oct 2013 01:13:27 -0700 (PDT)
Received: from EXHUB020-1.exch020.serverdata.net (exhub020-1.exch020.serverdata.net [206.225.164.28]) by ietfa.amsl.com (Postfix) with ESMTP id 2733B21E80B7 for <hybi@ietf.org>; Sun, 13 Oct 2013 01:13:23 -0700 (PDT)
Received: from EXVMBX020-12.exch020.serverdata.net ([169.254.3.240]) by EXHUB020-1.exch020.serverdata.net ([206.225.164.28]) with mapi; Sun, 13 Oct 2013 01:13:21 -0700
From: Tobias Oberstein <tobias.oberstein@tavendo.de>
To: Takeshi Yoshino <tyoshino@google.com>, Joakim Erdfelt <joakim@intalio.com>
Date: Sun, 13 Oct 2013 01:13:18 -0700
Thread-Topic: [hybi] permessage-deflate and missing asymmetric configurations
Thread-Index: Ac7FLZw7V4dA7qr2RN66+5XssbA6agCvaqAA
Message-ID: <634914A010D0B943A035D226786325D44469B06661@EXVMBX020-12.exch020.serverdata.net>
References: <CAG4zZZAqGcVP=4P9qfo2Gm3fbPHKntwZ5aF=hDePccfKnD4kWQ@mail.gmail.com> <02030518-6F55-4E50-9AB8-06C7540C8AE1@zaphoyd.com> <CAG4zZZCYkuQx40zn-wUBoeSecJ-NTDku-nD5-gkSSy-A1vhxNQ@mail.gmail.com> <CAH9hSJZugsZjJ7j7EoGseT9QauQ2bApK7OcWAtirCZ6b0SHwvA@mail.gmail.com>
In-Reply-To: <CAH9hSJZugsZjJ7j7EoGseT9QauQ2bApK7OcWAtirCZ6b0SHwvA@mail.gmail.com>
Accept-Language: de-DE, en-US
Content-Language: de-DE
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
acceptlanguage: de-DE, en-US
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
Cc: "hybi@ietf.org" <hybi@ietf.org>, Peter Thorson <webmaster@zaphoyd.com>
Subject: Re: [hybi] permessage-deflate and missing asymmetric configurations
X-BeenThere: hybi@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: Server-Initiated HTTP <hybi.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/hybi>, <mailto:hybi-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/hybi>
List-Post: <mailto:hybi@ietf.org>
List-Help: <mailto:hybi-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/hybi>, <mailto:hybi-request@ietf.org?subject=subscribe>
X-List-Received-Date: Sun, 13 Oct 2013 08:13:32 -0000

>>Was the idea of having compression level as a configurable ever on the table?
>Since each endpoint can choose any compression level as long as wbits and context mode are negotiated, I didn't include compression level negotiation.
 
Exactly.

We only need to negotiate parameters that must be agreed upon make the communication compatible - not every knob that is available at the compressor/decompressor within each endpoint.

Compression level is a useful knob .. but doesn't need to be negotiated.

>Rough plan was adding some attribute or method or overloading send() method of WebSocket to allow webapps to flip compression on/off.

Exposing an API for apps to control compression yes/no on a _per message_ basis is definitely worth: the app might have knowledge whether a given payload is compressible at all. E.g. when the app has encrypted the payload (for end-to-end privacy), it makes no sense to compress at WS level. Payload needs to be compressed before encryption.

/Tobias
 

v2.23.0 | Report a Bug | By Email