Re: [rtcweb] An input for discussing congestion control (Fwd: New Version Notification for draft-alvestrand-rtcweb-congestion-00.txt)
Varun Singh <vsingh.ietf@gmail.com> Mon, 19 September 2011 08:05 UTC
Return-Path: <vsingh.ietf@gmail.com>
X-Original-To: rtcweb@ietfa.amsl.com
Delivered-To: rtcweb@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id B9E3021F8B34 for <rtcweb@ietfa.amsl.com>; Mon, 19 Sep 2011 01:05:54 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -3.157
X-Spam-Level:
X-Spam-Status: No, score=-3.157 tagged_above=-999 required=5 tests=[AWL=-0.443, BAYES_00=-2.599, HTML_FONT_FACE_BAD=0.884, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_LOW=-1]
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 77-7PMGA6fsP for <rtcweb@ietfa.amsl.com>; Mon, 19 Sep 2011 01:05:53 -0700 (PDT)
Received: from mail-fx0-f44.google.com (mail-fx0-f44.google.com [209.85.161.44]) by ietfa.amsl.com (Postfix) with ESMTP id 24C7721F8B28 for <rtcweb@ietf.org>; Mon, 19 Sep 2011 01:05:52 -0700 (PDT)
Received: by fxd18 with SMTP id 18so3978590fxd.31 for <rtcweb@ietf.org>; Mon, 19 Sep 2011 01:08:15 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=references:from:in-reply-to:mime-version:date:message-id:subject:to :cc:content-type; bh=otmg+SvWf77GF2eUd0+Ta6DbFxjY3hVrLsuGTxECtdE=; b=EPuEz+u2KfB+5KQruAaTo5j3bf6wxeyY8p9fQ+ntiTjWRCWmwSn5+j80vpj99h9EVk fS+O9tDOF852dVBrvTozqtb9Vk03v0IyRdtoB9Ph/LhhK81jbJ3OKLq22hupQXyPP4R8 iMkG2B0p5bEt3asnO9wa+nehgtV52SKuJNYf8=
Received: by 10.223.10.84 with SMTP id o20mr1048763fao.25.1316419694870; Mon, 19 Sep 2011 01:08:14 -0700 (PDT)
References: <4E649FBD.1090001@alvestrand.no> <4E734E89.5010105@ericsson.com> <4E766C4C.2020201@jesup.org> <CAEdus3LcjV9x+gLdZm5vwKhh-ge6xzfWSEB_NxcHe1Gz_5DZ8g@mail.gmail.com> <4E76F544.1040108@jesup.org> <CAOhzyfnGzQ36H+0fzGVNpnpDrapNgMCC4Dr1LO_sr-vDUJsi4A@mail.gmail.com>
From: Varun Singh <vsingh.ietf@gmail.com>
In-Reply-To: <CAOhzyfnGzQ36H+0fzGVNpnpDrapNgMCC4Dr1LO_sr-vDUJsi4A@mail.gmail.com>
Mime-Version: 1.0 (1.0)
Date: Mon, 19 Sep 2011 11:08:09 +0300
Message-ID: <-2862138070495616930@unknownmsgid>
To: Henrik Lundin <hlundin@google.com>
Content-Type: multipart/alternative; boundary="0015174795c649bfa704ad46d86b"
Cc: Randell Jesup <randell-ietf@jesup.org>, "rtcweb@ietf.org" <rtcweb@ietf.org>
Subject: Re: [rtcweb] An input for discussing congestion control (Fwd: New Version Notification for draft-alvestrand-rtcweb-congestion-00.txt)
X-BeenThere: rtcweb@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: Real-Time Communication in WEB-browsers working group list <rtcweb.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/rtcweb>, <mailto:rtcweb-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/rtcweb>
List-Post: <mailto:rtcweb@ietf.org>
List-Help: <mailto:rtcweb-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/rtcweb>, <mailto:rtcweb-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 19 Sep 2011 08:05:54 -0000
I'd be interested in this as well. Regards, Varun ---- http://www.netlab.tkk.fi/~varun On 19.9.2011, at 11.04, Henrik Lundin <hlundin@google.com> wrote: Add me to the bof members list. /Henrik L On Mon, Sep 19, 2011 at 9:54 AM, Randell Jesup <randell-ietf@jesup.org>wrote: > Open question to the list: should the congestion-control-geeks discuss > here on the > list the nitty-gritty details required to build the requirements and > especially to design > and debate a possible proposed "baseline" congestion-control algorithm? > > We can certainly do that detailed discussion by email and come back with a > draft; I had been planning to do it by email, but recent discussion on > rtcweb > made me think I should ask for opinions on this. Given the structure, if > there's > any significant support for "on-the-list" I'll do that. Realize though > that they may > get pretty long and detailed without really touching on the larger issues > being > discussed here. > > Right now the bof members to discuss this and propose a draft would be > myself, > Harald, Justin, Stefan Holmer and Magnus. > > > On 9/19/2011 3:06 AM, Stefan Holmer wrote: > > On Mon, Sep 19, 2011 at 12:10 AM, Randell Jesup <randell-ietf@jesup.org>wrote: > >> On 9/16/2011 9:26 AM, Magnus Westerlund wrote: >> >>> 1. Section 3: As delay based congestion control has been tried a number >>> of times and meet with less than stellar success I wonder if you have >>> any understanding of how this relates to the issues previously >>> encountered: >>> >> Do you have any pointers to these earlier attempts? My separate >> experience >> with this class has been extremely successful, though perhaps with a set >> of >> real-world use-cases that don't cover the situations you're referring to. >> My understanding is that Radvision's NetSense is very similar from their >> description of it. >> >> > I'm interested in any references you may have as well. > > > > I doubt you'll find many/any, as the first published discussion I saw of > delay-sensing > congestion control for RTP data was Radvision's posts about Netsense last > year > and in their Android webcasts; and that was pretty detail-free until their > recent > blog posts. There's plenty of un-published experience with them at various > companies > I believe.... Not just Google and Radvision. > > > > >> >> - Stability (especially on short RTTs) >>> - How it competes with TCP flows, which was a real issues for TCP Vegas >>> but may be less of an issue here. >>> >> Perhaps Google can comment here about what tests they've done. If >> anything, >> this class of algorithm when faced with aggressive TCP flows will >> eventually >> have problems, because TCP will tend to fill up the buffers at the >> bottleneck. >> Since this algorithm senses buffers starting to fill up, it will tend to >> back >> off before TCP is likely to see a loss event. Now, it's more complex than >> that of course, and multiple flows make it more complex still. It's also >> sensitive to the adaptation rate of this algorithm and speed of backoff. >> If I remember, TFRC tends to back off more slowly than TCP but also >> increase >> more slowly; I suspect Google's algorithm is similar. >> > > As you're saying, it will always be hard for delay based congestion > control algorithms to compete with a packet loss based algorithm. The delay > based algorithm will detect over-use much earlier than the packet loss based > one, and that's basically what we've seen in the tests we've been running as > well. I do think we would benefit from more tests in this area. For > instance, we might want to go with an additive increase approach rather than > the current one which is multiplicative, this would likely help improve the > algorithms self fairness as well. > > > Probably; additive increase is probably better, or possible using a > fraction-of- > predicted-bandwidth increase. If you use additive increase, it should > probably be > partly proportional to the maximum "good" bandwidth seen during the > connection. > This provides some needed scaling of the ramp-up rate to the absolute > magnitude > of bandwidth available. > > > -- > Randell Jesuprandell-ietf@jesup.org > > > _______________________________________________ > rtcweb mailing list > rtcweb@ietf.org > https://www.ietf.org/mailman/listinfo/rtcweb > > -- Henrik Lundin | WebRTC Software Eng | hlundin@google.com | +46 70 646 13 41 _______________________________________________ rtcweb mailing list rtcweb@ietf.org https://www.ietf.org/mailman/listinfo/rtcweb
- [rtcweb] An input for discussing congestion contr… Harald Alvestrand
- Re: [rtcweb] An input for discussing congestion c… Randell Jesup
- Re: [rtcweb] An input for discussing congestion c… Harald Alvestrand
- Re: [rtcweb] An input for discussing congestion c… Magnus Westerlund
- Re: [rtcweb] An input for discussing congestion c… Randell Jesup
- Re: [rtcweb] An input for discussing congestion c… Stefan Holmer
- Re: [rtcweb] An input for discussing congestion c… Randell Jesup
- Re: [rtcweb] An input for discussing congestion c… Henrik Lundin
- Re: [rtcweb] An input for discussing congestion c… Varun Singh
- Re: [rtcweb] An input for discussing congestion c… Henrik Lundin
- Re: [rtcweb] An input for discussing congestion c… Tim Panton
- Re: [rtcweb] An input for discussing congestion c… Henrik Lundin
- Re: [rtcweb] An input for discussing congestion c… Varun Singh
- Re: [rtcweb] An input for discussing congestion c… Randell Jesup
- Re: [rtcweb] An input for discussing congestion c… Soo-Hyun Choi
- Re: [rtcweb] An input for discussing congestion c… Henrik Lundin
- Re: [rtcweb] An input for discussing congestion c… Soo-Hyun Choi
- Re: [rtcweb] An input for discussing congestion c… Harald Alvestrand
- Re: [rtcweb] An input for discussing congestion c… Soo-Hyun Choi
- Re: [rtcweb] An input for discussing congestion c… Harald Alvestrand
- Re: [rtcweb] An input for discussing congestion c… Dzonatas Sol
- Re: [rtcweb] An input for discussing congestion c… Randell Jesup
- Re: [rtcweb] An input for discussing congestion c… Soo-Hyun Choi
- Re: [rtcweb] An input for discussing congestion c… Harald Alvestrand
- Re: [rtcweb] An input for discussing congestion c… Randell Jesup
- Re: [rtcweb] An input for discussing congestion c… Jim Gettys
- Re: [rtcweb] An input for discussing congestion c… Henrik Lundin
- Re: [rtcweb] An input for discussing congestion c… Ingemar Johansson S
- Re: [rtcweb] An input for discussing congestion c… Henrik Lundin
- Re: [rtcweb] An input for discussing congestion c… Randell Jesup
- Re: [rtcweb] An input for discussing congestion c… Stefan Holmer
- Re: [rtcweb] An input for discussing congestion c… Soo-Hyun Choi