From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from korolev.univ-paris7.fr (korolev.univ-paris7.fr [IPv6:2001:660:3301:8000::1:2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 93A653B2A0; Thu, 28 Apr 2016 09:37:50 -0400 (EDT) Received: from potemkin.univ-paris7.fr (potemkin.univ-paris7.fr [IPv6:2001:660:3301:8000::1:1]) by korolev.univ-paris7.fr (8.14.4/8.14.4/relay1/56228) with ESMTP id u3SDbhkm002440 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Thu, 28 Apr 2016 15:37:43 +0200 Received: from mailhub.math.univ-paris-diderot.fr (mailhub.math.univ-paris-diderot.fr [81.194.30.253]) by potemkin.univ-paris7.fr (8.14.4/8.14.4/relay2/56228) with ESMTP id u3SDbhmg028122; Thu, 28 Apr 2016 15:37:43 +0200 Received: from mailhub.math.univ-paris-diderot.fr (localhost [127.0.0.1]) by mailhub.math.univ-paris-diderot.fr (Postfix) with ESMTP id 62D1461FF3; Thu, 28 Apr 2016 15:37:43 +0200 (CEST) X-Virus-Scanned: amavisd-new at math.univ-paris-diderot.fr Received: from mailhub.math.univ-paris-diderot.fr ([127.0.0.1]) by mailhub.math.univ-paris-diderot.fr (mailhub.math.univ-paris-diderot.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id Nc4A3eY-Qbx7; Thu, 28 Apr 2016 15:37:42 +0200 (CEST) Received: from trurl.pps.univ-paris-diderot.fr (col75-1-78-194-40-74.fbxo.proxad.net [78.194.40.74]) (Authenticated sender: jch) by mailhub.math.univ-paris-diderot.fr (Postfix) with ESMTPSA id 0E0FA61FE8; Thu, 28 Apr 2016 15:37:41 +0200 (CEST) Date: Thu, 28 Apr 2016 15:37:43 +0200 Message-ID: <87oa8tyhug.wl-jch@pps.univ-paris-diderot.fr> From: Juliusz Chroboczek To: dpreed@reed.com Cc: "Aaron Wood" , make-wifi-fast@lists.bufferbloat.net, "cerowrt-devel@lists.bufferbloat.net" , "babel-users@lists.alioth.debian.org" In-Reply-To: <1461849006.60252745@apps.rackspace.com> References: <1461849006.60252745@apps.rackspace.com> User-Agent: Wanderlust/2.15.9 MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.7 (korolev.univ-paris7.fr [IPv6:2001:660:3301:8000::1:2]); Thu, 28 Apr 2016 15:37:43 +0200 (CEST) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.7 (potemkin.univ-paris7.fr [194.254.61.141]); Thu, 28 Apr 2016 15:37:43 +0200 (CEST) X-Miltered: at korolev with ID 57221227.002 by Joe's j-chkmail (http : // j-chkmail dot ensmp dot fr)! X-Miltered: at potemkin with ID 57221227.001 by Joe's j-chkmail (http : // j-chkmail dot ensmp dot fr)! X-j-chkmail-Enveloppe: 57221227.002 from potemkin.univ-paris7.fr/potemkin.univ-paris7.fr/null/potemkin.univ-paris7.fr/ X-j-chkmail-Enveloppe: 57221227.001 from mailhub.math.univ-paris-diderot.fr/mailhub.math.univ-paris-diderot.fr/null/mailhub.math.univ-paris-diderot.fr/ X-j-chkmail-Score: MSGID : 57221227.002 on korolev.univ-paris7.fr : j-chkmail score : . : R=. U=. O=. B=0.000 -> S=0.000 X-j-chkmail-Score: MSGID : 57221227.001 on potemkin.univ-paris7.fr : j-chkmail score : . : R=. U=. O=. B=0.000 -> S=0.000 X-j-chkmail-Status: Ham X-j-chkmail-Status: Ham Subject: Re: [Make-wifi-fast] [Babel-users] perverse powersave bug with sta/ap mode X-BeenThere: make-wifi-fast@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 28 Apr 2016 13:37:50 -0000 > Multicast is seductive to designers who ignore the realities of > propagation and channel coding issues, because they think it works one > way, but the reality is quite different. Hold on. Mulsticast is used for two distinct purposes: for broadcast-style applications (streaming), and for discovery (ARP, ND, mDNS, and of course the Hello beaconing of routing protocols). For broadcast-style applications, multicast can be replaced with multiple unicast streams, as Netflix shows, although this is best done at the routers rather than at the senders, since this allows building a single distribution tree without the need for application-layer proxies ("CDNs"). For discovery, multicast is unavoidable -- there's simply no way you're going to send a unicast to a node that you haven't discovered yet. -- Juliusz