Re: [v6ops] ref Hosts dont MLD to join LL groups
Enno Rey <erey@ernw.de> Thu, 23 July 2015 13:01 UTC
Return-Path: <erey@ernw.de>
X-Original-To: v6ops@ietfa.amsl.com
Delivered-To: v6ops@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 7964D1AC3CE for <v6ops@ietfa.amsl.com>; Thu, 23 Jul 2015 06:01:56 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.601
X-Spam-Level:
X-Spam-Status: No, score=-2.601 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, RCVD_IN_DNSWL_LOW=-0.7, SPF_PASS=-0.001] autolearn=ham
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id iW3EvyAw7RDQ for <v6ops@ietfa.amsl.com>; Thu, 23 Jul 2015 06:01:53 -0700 (PDT)
Received: from mx1.ernw.net (mx1.ernw.net [62.159.96.78]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 9B05E1A0173 for <v6ops@ietf.org>; Thu, 23 Jul 2015 06:01:53 -0700 (PDT)
Received: from mh1.ernw.net (unknown [IPv6:fd00:2001:0:d001::10]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (Client CN "mh1.ernw.net", Issuer "ernw ca1" (verified OK)) by mx1.ernw.net (Postfix) with ESMTPS id A046A15EC2E for <v6ops@ietf.org>; Thu, 23 Jul 2015 15:04:04 +0200 (CEST)
Received: from ws25.ernw.net (ws25.ernw.net [172.31.100.10]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (Client CN "ws25.ernw.net", Issuer "ernw ca1" (verified OK)) by mh1.ernw.net (Postfix) with ESMTPS id 305EF5F8 for <v6ops@ietf.org>; Thu, 23 Jul 2015 15:01:52 +0200 (CEST)
Received: by ws25.ernw.net (Postfix, from userid 1001) id 0D89BC4878; Thu, 23 Jul 2015 15:01:52 +0200 (CEST)
Date: Thu, 23 Jul 2015 15:01:52 +0200
From: Enno Rey <erey@ernw.de>
To: v6ops@ietf.org
Message-ID: <20150723130151.GA57117@ernw.de>
References: <55AE42A4.8020908@gmail.com> <5CD05758-D7B7-476D-9936-E5A1D0614AF8@employees.org> <55B0D356.7070505@gmail.com> <6666FED5-227B-496F-B5F5-2883A12F9B96@employees.org> <55B0DB2B.1030703@gmail.com> <20150723122710.GX57117@ernw.de> <55B0E2C5.2060309@gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Disposition: inline
In-Reply-To: <55B0E2C5.2060309@gmail.com>
User-Agent: Mutt/1.5.21 (2010-09-15)
Archived-At: <http://mailarchive.ietf.org/arch/msg/v6ops/Tob0Jg3bdEb-mEZVtZUfYoo4eZE>
Subject: Re: [v6ops] ref Hosts dont MLD to join LL groups
X-BeenThere: v6ops@ietf.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: v6ops discussion list <v6ops.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/v6ops>, <mailto:v6ops-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/v6ops/>
List-Post: <mailto:v6ops@ietf.org>
List-Help: <mailto:v6ops-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/v6ops>, <mailto:v6ops-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 23 Jul 2015 13:01:56 -0000
Hi, > > Inform the sender willingnes to be part of the group. If not part of > group, then sender will not send it. Same concept at L2 and at L3. wrong. the sender of a MC message just sends it out, regardless if somebody listens or not. the router(s) helping to distribute this message (in case of interdomain MC) only have to know (= are interested) if there's at least one interested listener on an adjacent link. neither the sender nor the router(s) have any interest (or need to have that) in individual listeners. > > > > strictly speaking MLD as a whole is only needed for interdomain > > multicast anyway. > > Disagree - beyond just interdomain multicast, Ethernet has link-layer > multicast builtin. There is no 'broadcast' address anymore in Ethernet > since some time, replaced by 'multicast': supposedly better at saving > battery and other advantages. > > > on the local link you join a MC group by kind-of self declaration > > ("hey I consider myself part of that group > > That is an Ethernet message. no. that's a decision taken somewhere in the software/stack. no need for any packet here. > > Some cards send that message, others don't. All should. > > > so I'm interested in > > certain traffic and hence instruct my stack to listen to/process > > packets with certain addresses"). no need of MLD for that action. > > How does the Ethernet layer know this is a Router, and not a Host? Only > by knowing that it can join the all-hosts or all-routers link-layer > address. And only the IP stack knows whether it's a Host or a Router. > So the IP stack should tell the Ethernet layer to make that link-layer join. which it does, as a stack-internal decision. "once I'm a router get me everything sent to ff02::1/33:33:00:00:00:01. in addition - given I'm a node anyway - get me everything for ff02::2". no need to send any packet for all this. best Enno > > Yours, > > Alex > > > but > > "joining" on the local-link doesn't need MLD. > > > > best > > > > Enno > > > > > > > > > > > >> > >> Alex > >> > >> Le 23/07/2015 13:51, Ole Troan a ??crit : > >>> Alexandru, > >>> > >>> I???m afraid I couldn???t interpret your message. would someone > >>> else be able to translate? > >>> > >>> cheers, Ole > >>> > >>>>> > >>>>> I do wonder if we should expand that exception to all > >>>>> link-scope multicast addresses. > >>>>> > >>>> > >>>> I would beg to disagree. > >>>> > >>>> If we expand that to all link-scoped groups, may lead to > >>>> dismantling IPv6 dependence on 33::1 - ff:ff:ff:ff:ff would be > >>>> sufficient. > >>>> > >>>> My oppinion would rather be to modify the MLD RFC to mandate > >>>> MLD joins for all scopes. > >>>> > >>>> Ethernet has primitives for joining the corresponding > >>>> link-layer groups, and in some cases they are used. Maybe all > >>>> should use them. > >>>> > >>>>> the bridge implementors I speak to tell me that they don???t > >>>>> have enough state to do MLD snooping for link-local scoped > >>>>> multicast addresses anyway... > >>>> > >>>> This may be dumb from my side, but why dont bridge > >>>> implementers use link-layer multicast? They shouldnt implement > >>>> MLD, and not snoop it. The Hosts should send the necessary > >>>> link-layer multicast joins (triggered by themselves sending MLD > >>>> REPORT for these groups) to the bridge addresses. > >>>> > >>>> Alex > >>>> > >>>>> cheers, Ole > >>> > >> > >> _______________________________________________ v6ops mailing list > >> v6ops@ietf.org https://www.ietf.org/mailman/listinfo/v6ops > > > > _______________________________________________ > v6ops mailing list > v6ops@ietf.org > https://www.ietf.org/mailman/listinfo/v6ops -- Enno Rey ERNW GmbH - Carl-Bosch-Str. 4 - 69115 Heidelberg - www.ernw.de Tel. +49 6221 480390 - Fax 6221 419008 - Cell +49 173 6745902 Handelsregister Mannheim: HRB 337135 Geschaeftsfuehrer: Enno Rey ======================================================= Blog: www.insinuator.net || Conference: www.troopers.de Twitter: @Enno_Insinuator =======================================================
- [v6ops] ref Hosts dont MLD to join LL groups Alexandru Petrescu
- Re: [v6ops] ref Hosts dont MLD to join LL groups Ole Troan
- Re: [v6ops] ref Hosts dont MLD to join LL groups Enno Rey
- Re: [v6ops] ref Hosts dont MLD to join LL groups Andrew 👽 Yourtchenko
- Re: [v6ops] ref Hosts dont MLD to join LL groups Alexandru Petrescu
- Re: [v6ops] ref Hosts dont MLD to join LL groups Ole Troan
- Re: [v6ops] ref Hosts dont MLD to join LL groups Alexandru Petrescu
- Re: [v6ops] ref Hosts dont MLD to join LL groups Enno Rey
- Re: [v6ops] ref Hosts dont MLD to join LL groups Alexandru Petrescu
- Re: [v6ops] ref Hosts dont MLD to join LL groups Enno Rey
- Re: [v6ops] ref Hosts dont MLD to join LL groups Alexandru Petrescu
- Re: [v6ops] ref Hosts dont MLD to join LL groups Owen DeLong
- Re: [v6ops] ref Hosts dont MLD to join LL groups Owen DeLong
- Re: [v6ops] ref Hosts dont MLD to join LL groups Alexandru Petrescu
- Re: [v6ops] ref Hosts dont MLD to join LL groups Owen DeLong