Re: You asked about multicast scope

Iljitsch van Beijnum <iljitsch@muada.com> Thu, 29 March 2012 12:52 UTC

Return-Path: <iljitsch@muada.com>
X-Original-To: ipv6@ietfa.amsl.com
Delivered-To: ipv6@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id AC1AD21F85D3; Thu, 29 Mar 2012 05:52:35 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -102.6
X-Spam-Level:
X-Spam-Status: No, score=-102.6 tagged_above=-999 required=5 tests=[AWL=0.000, BAYES_00=-2.599, NO_RELAYS=-0.001, USER_IN_WHITELIST=-100]
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 H+l4eI7e1H3q; Thu, 29 Mar 2012 05:52:35 -0700 (PDT)
Received: from sequoia.muada.com (sequoia.muada.com [IPv6:2001:1af8:3100:a006:1::]) by ietfa.amsl.com (Postfix) with ESMTP id 26CE421F85CF; Thu, 29 Mar 2012 05:52:33 -0700 (PDT)
Received: from [IPv6:2001:df8::80:4c8c:40e7:73c:3dc6] ([IPv6:2001:df8:0:80:4c8c:40e7:73c:3dc6]) (authenticated bits=0) by sequoia.muada.com (8.13.3/8.13.3) with ESMTP id q2TCqDwR097139 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO); Thu, 29 Mar 2012 14:52:14 +0200 (CEST) (envelope-from iljitsch@muada.com)
Subject: Re: You asked about multicast scope
Mime-Version: 1.0 (Apple Message framework v1257)
Content-Type: text/plain; charset=us-ascii
From: Iljitsch van Beijnum <iljitsch@muada.com>
In-Reply-To: <4F74526D.6070003@innovationslab.net>
Date: Thu, 29 Mar 2012 14:52:29 +0200
Content-Transfer-Encoding: quoted-printable
Message-Id: <3042ADDB-95B9-4160-8BF1-F2E9E6C5A2A8@muada.com>
References: <FF493C74-28AA-4B3D-ABBA-38294010230F@cisco.com> <BEEE8260-1AC5-41C9-A9D7-EFF1CCF5CBB4@muada.com> <DA8DC604-C36C-4D59-931A-B7C22F8E2051@cisco.com> <00B02ED4-4D6F-4B67-B548-D186C1B3B2CA@muada.com> <2AA4DD9C-DD38-422C-8483-FF295C086E11@cisco.com> <848F4FFF-2303-4E49-81CB-A0BD9180F31D@muada.com> <CABOxzu0yC6Y4gFXKACDSdAy+GNzWGZStjpVMUB5HWXjBoXKUxw@mail.gmail.com> <4F74447E.6020506@venaas.com> <4F74526D.6070003@innovationslab.net>
To: Brian Haberman <brian@innovationslab.net>
X-Mailer: Apple Mail (2.1257)
Cc: pcp@ietf.org, 6man 6man <ipv6@ietf.org>, Fred Baker <fred@cisco.com>
X-BeenThere: ipv6@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: "IPv6 Maintenance Working Group \(6man\)" <ipv6.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ipv6>, <mailto:ipv6-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/ipv6>
List-Post: <mailto:ipv6@ietf.org>
List-Help: <mailto:ipv6-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ipv6>, <mailto:ipv6-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 29 Mar 2012 12:52:35 -0000

On 29 Mar 2012, at 14:15 , Brian Haberman wrote:

> It is not an assumption, it is stately quite clearly in the Scoped Addressing Architecture (RFC 4007).  From Section 5 :

>      A zone of a given scope (less than global) falls completely within
>      zones of larger scope.  That is, a smaller scope zone cannot
>      include more topology than would any larger scope zone with which
>      it shares any links or interfaces.

Brian, Stig, thanks for the help.

Fred: I think what would be best is to define a "service provider" scope that is smaller than global, and larger than organization. These would be defined to be forwarded to ISPs by default, although organizations that don't want that can always filter them at the desired boundary.

That way, the clients can always use a fixed scope = fixed multicast group, avoiding the need for discovery or configuration here.