Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands over IPv4 MPLS using IPv6 Provider Edge Routers (6PE)' to Proposed Standard
Yakov Rekhter <yakov@juniper.net> Fri, 25 August 2006 18:28 UTC
Received: from [127.0.0.1] (helo=stiedprmman1.va.neustar.com) by megatron.ietf.org with esmtp (Exim 4.43) id 1GGgPo-0006BS-Be; Fri, 25 Aug 2006 14:28:24 -0400
Received: from [10.91.34.44] (helo=ietf-mx.ietf.org) by megatron.ietf.org with esmtp (Exim 4.43) id 1GGgPn-0006B7-CV; Fri, 25 Aug 2006 14:28:23 -0400
Received: from colo-dns-ext1.juniper.net ([207.17.137.57]) by ietf-mx.ietf.org with esmtp (Exim 4.43) id 1GGgPl-0008KI-Ui; Fri, 25 Aug 2006 14:28:23 -0400
Received: from merlot.juniper.net (merlot.juniper.net [172.17.27.10]) by colo-dns-ext1.juniper.net (8.11.3/8.9.3) with ESMTP id k7PISLX24860; Fri, 25 Aug 2006 11:28:21 -0700 (PDT) (envelope-from yakov@juniper.net)
Received: from juniper.net (sapphire.juniper.net [172.17.28.108]) by merlot.juniper.net (8.11.3/8.11.3) with ESMTP id k7PISFg11936; Fri, 25 Aug 2006 11:28:15 -0700 (PDT) (envelope-from yakov@juniper.net)
Message-Id: <200608251828.k7PISFg11936@merlot.juniper.net>
To: David Ward <dward@cisco.com>
Subject: Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands over IPv4 MPLS using IPv6 Provider Edge Routers (6PE)' to Proposed Standard
In-Reply-To: Your message of "Fri, 25 Aug 2006 12:33:49 CDT." <C1149EAD.8061A%dward@cisco.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-ID: <46311.1156530495.1@juniper.net>
Date: Fri, 25 Aug 2006 11:28:15 -0700
From: Yakov Rekhter <yakov@juniper.net>
X-Spam-Score: 0.0 (/)
X-Scan-Signature: 769a46790fb42fbb0b0cc700c82f7081
Cc: idr@ietf.org, Bill Fenner <fenner@research.att.com>, Yakov Rekhter <yakov@juniper.net>, "Durand, Alain" <Alain_Durand@cable.comcast.com>, IESG <iesg@ietf.org>, softwires@ietf.org, "Mark Townsley (townsley)" <townsley@cisco.com>, Sam Hartman <hartmans-ietf@mit.edu>
X-BeenThere: idr@ietf.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Inter-Domain Routing <idr.ietf.org>
List-Unsubscribe: <https://www1.ietf.org/mailman/listinfo/idr>, <mailto:idr-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www1.ietf.org/pipermail/idr>
List-Post: <mailto:idr@ietf.org>
List-Help: <mailto:idr-request@ietf.org?subject=help>
List-Subscribe: <https://www1.ietf.org/mailman/listinfo/idr>, <mailto:idr-request@ietf.org?subject=subscribe>
Errors-To: idr-bounces@ietf.org
David, > Yakov, Bill - > > Having read the document I have some initial comments. First, 6PE is an > excellent solution. Overstating the obvious (perhaps my greatest talent), > this is a solution for the subset of softwire problems that would be used > for 6-over-4 when the encaps policy is "always use MPLS" and there are no > security requirements. I will leave the question of 'no security > requirements' for this solution to others. > > The major deficiency from a softwires vantage point is that the v4 NH gets > encoded in a v6 format, but semantically it's v4 and this encoding trick > doesn't work when you're doing v6 over v4. This is not to say the solution > doesn't work but, since softwires has to solve both v4 over v6 and v6 over > v4 (and variants including VPNs); I strongly urge that we don't have > multiple techniques to derive the AF of the NH. As we move forward, I agree with the goal of having a single technique to derive AF of the NH within the context of MP_REACH/MP_UNREACH. > The current advancement of multiple techniques that require either encoding > or length-check should be cleared up and made obvious and consistent. > > I recommend some number of bits (or a byte) be used to state clearly what the > AF of the NH is and leave in original encoding. A capability can be added to > make sure that a peer can understand the new bits. Of course, I am looking > for the minimal change to the doc and to BGP but, this matter needs to be > discussed. The assumptions becoming embedded in the techniques of how to > figure out what the actual AF of the NH could be easily cleared up w/ the > suggestion of just very small number of bits and a capability in BGP. While having "new bits" may be sufficient, it is by no means necessary. This is because the current/original encoding already provides a way to distinguish between IPv4 and IPv6 addresses in the NH of MP_REACH/MP_UNREACH. I am referring to the approach already used in several documents approved by the IETF (e.g., draft-ietf-l2vpn-signaling, draft-ietf-l3vpn-rt-constrain, draft-ietf-l2vpn-vpls-bgp) where the NH Length field is used to distinguish between IPv4 and IPv6 as the NH. And just for completeness, the current/original encoding provides yet another way to distingush between IPv4 and IPv6 as the NH addresses - use two different SAFIs to distinguish between IPv4 and IPv6 as the NH. However, I am not aware of any IETF technologies that use this approach. Yakov. _______________________________________________ Idr mailing list Idr@ietf.org https://www1.ietf.org/mailman/listinfo/idr
- [Idr] Last Call: 'Connecting IPv6 Islands over IP… The IESG
- [Idr] Re: Last Call: 'Connecting IPv6 Islands ove… Bill Fenner
- [Idr] Re: Last Call: 'Connecting IPv6 Islands ove… Bill Fenner
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… Yakov Rekhter
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… David Ward
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… David Ward
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… Yakov Rekhter
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… David Ward
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… Yakov Rekhter
- Re: [Softwires] Re: [Idr] Re: Last Call: 'Connect… Pekka Savola
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… David Ward
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… Yakov Rekhter
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… David Ward
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… Eric Rosen
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… Francois Le Faucheur
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… David Ward
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… Francois Le Faucheur
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… Robert Raszuk
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… Francois Le Faucheur
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… Robert Raszuk
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… Francois Le Faucheur
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… Robert Raszuk
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… Francois Le Faucheur
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… David Ward
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… Francois Le Faucheur
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… Yakov Rekhter
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… Yakov Rekhter
- Re: [Idr] Re: Last Call: 'Connecting IPv6 Islands… Francois Le Faucheur