Re: [v6ops] Extension Headers / Impact on Security Devices

"Stefano Previdi (sprevidi)" <sprevidi@cisco.com> Thu, 28 May 2015 16:43 UTC

Return-Path: <sprevidi@cisco.com>
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 2DA221A0264 for <v6ops@ietfa.amsl.com>; Thu, 28 May 2015 09:43:57 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -14.511
X-Spam-Level:
X-Spam-Status: No, score=-14.511 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, RCVD_IN_DNSWL_HI=-5, SPF_PASS=-0.001, T_RP_MATCHES_RCVD=-0.01, USER_IN_DEF_DKIM_WL=-7.5] 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 wixUXowUJ9u2 for <v6ops@ietfa.amsl.com>; Thu, 28 May 2015 09:43:55 -0700 (PDT)
Received: from rcdn-iport-5.cisco.com (rcdn-iport-5.cisco.com [173.37.86.76]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 9858E1A1A40 for <v6ops@ietf.org>; Thu, 28 May 2015 09:43:55 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=cisco.com; i=@cisco.com; l=2561; q=dns/txt; s=iport; t=1432831435; x=1434041035; h=from:to:cc:subject:date:message-id:references: in-reply-to:content-id:content-transfer-encoding: mime-version; bh=i1OmtaVh+sQ5eJfw7BHAhyshUv/GjqPoUxN1doPZ3n4=; b=bShU/rIw3f5Fm86zKPELR/RBanb3N+01nffyDiv4JDLTMrnV2b25okRP IJ2552BQTFNp8RBuPp51EyrQ5h/2uK5oK5zMvt/q5tFQRgyGIf/XjpK/t i+qqaUkk2NC8f3gbFUB04i3trniK4mB8w5LgvYsgew+2jLxr5FHgwbsa/ U=;
X-IronPort-Anti-Spam-Filtered: true
X-IronPort-Anti-Spam-Result: A0ASBQBmRWdV/5tdJa1cgxBUUQ0GvQSCPwqFdwKBTEwBAQEBAQGBC4QiAQEBAwEBAQELVwkLBQsCAQgYLicLJQIEDgWIJQgN1ToBAQEBAQEBAQEBAQEBAQEBAQEBAQETBItDhFMzB4MXgRYFjAqEQoI8iw+BKZItg1kjgWaCEm+BRoEBAQEB
X-IronPort-AV: E=Sophos;i="5.13,513,1427760000"; d="scan'208";a="423382486"
Received: from rcdn-core-4.cisco.com ([173.37.93.155]) by rcdn-iport-5.cisco.com with ESMTP; 28 May 2015 16:43:52 +0000
Received: from xhc-aln-x01.cisco.com (xhc-aln-x01.cisco.com [173.36.12.75]) by rcdn-core-4.cisco.com (8.14.5/8.14.5) with ESMTP id t4SGhqp5005535 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=FAIL); Thu, 28 May 2015 16:43:52 GMT
Received: from xmb-rcd-x01.cisco.com ([169.254.1.227]) by xhc-aln-x01.cisco.com ([173.36.12.75]) with mapi id 14.03.0195.001; Thu, 28 May 2015 11:43:52 -0500
From: "Stefano Previdi (sprevidi)" <sprevidi@cisco.com>
To: "Eric Vyncke (evyncke)" <evyncke@cisco.com>
Thread-Topic: [v6ops] Extension Headers / Impact on Security Devices
Thread-Index: AQHQjwOUSoUfhjfqOU2VSvc4/QdUh52O8gsqgABXE4CAAAaigIAABSaAgAAHmwCAAHnhgIACNimA///0LwA=
Date: Thu, 28 May 2015 16:43:51 +0000
Message-ID: <598DB10C-41F9-4297-BD43-EA1F99982AED@cisco.com>
References: <555AB8FA.2080405@si6networks.com> <F6AA9AEA-49F0-488C-84EA-50BE103987C8@nominum.com> <555B8622.5000806@isi.edu> <555BA184.8080701@gmail.com> <555BA43F.8010303@isi.edu> <5564FB74.5020303@gmail.com> <5564FE3F.4050102@isi.edu> <556503CF.4030101@gmail.com> <55650821.4060907@isi.edu> <55650E82.3090407@gmail.com> <20150527073943.GA54385@Space.Net> <D18CFF39.4C411%evyncke@cisco.com>
In-Reply-To: <D18CFF39.4C411%evyncke@cisco.com>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
x-originating-ip: [10.61.215.40]
Content-Type: text/plain; charset="iso-8859-1"
Content-ID: <44E977BA8882C84F96DA113BE7582C23@emea.cisco.com>
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
Archived-At: <http://mailarchive.ietf.org/arch/msg/v6ops/xEVNipU5jWEXjr29ZeiuWmTMHQg>
X-Mailman-Approved-At: Fri, 29 May 2015 09:56:19 -0700
Cc: "Mark Townsley (townsley)" <townsley@cisco.com>, "v6ops@ietf.org" <v6ops@ietf.org>
Subject: Re: [v6ops] Extension Headers / Impact on Security Devices
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: <http://www.ietf.org/mail-archive/web/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, 28 May 2015 16:43:57 -0000

On May 28, 2015, at 5:26 PM, "Eric Vyncke (evyncke)" <evyncke@cisco.com>
 wrote:

> Segment Routing Header is currently drafted as another type of routing
> header and are drafted to be inserted either by the source or by the
> ingress router of a SR-configured domain (then being removed at the exit
> of the SR-domain).


correct.

packet classification at ingress may result into a new SRH (segment routing header).
Very similar (well, mostly the same) to what ipv4/6 packet get with a label stack.

s.



> Destination Option is not useful here as it is
> inspected/processed only by the destination while the intent of SR is to
> have this information processed by a couple of intermediate routers (which
> have a specific configuration as SRH is not enabled by default).
> 
> Of course, this causes MTU issues (pretty much like MPLS but at a
> different layer) within one domain which is solvable. The performance
> issues need to be handled (as Joe wrote). But, as long as the pros/cons
> balance is on the pro side, then it is valuable.
> 
> -éric
> 
> 
> On 27/05/15 09:39, "Gert Doering" <gert@space.net> wrote:
> 
>> Hi,
>> 
>> On Wed, May 27, 2015 at 12:23:30PM +1200, Brian E Carpenter wrote:
>>>> FWIW, I don't see anything that prohibits adding headers either.
>>> 
>>> "With one exception, extension headers are not examined or processed
>>> by any node along a packet's delivery path, until the packet reaches
>>> the node (or each of the set of nodes, in the case of multicast)
>>> identified in the Destination Address field of the IPv6 header."
>>> 
>>> To me that clearly implies not adding (which is a form of processing).
>> 
>> So how do the SR folks handle that?  From what I heard, the intended
>> deployment really is "inside your administrative domain, SR headers get
>> added, processed, and when the packet leaves your domain, they can be
>> (optionally) removed again to not upset your neighbours"...
>> 
>> Gert Doering
>>       -- NetMaster
>> -- 
>> have you enabled IPv6 on something today...?
>> 
>> SpaceNet AG                        Vorstand: Sebastian v. Bomhard
>> Joseph-Dollinger-Bogen 14          Aufsichtsratsvors.: A.
>> Grundner-Culemann
>> D-80807 Muenchen                   HRB: 136055 (AG Muenchen)
>> Tel: +49 (0)89/32356-444           USt-IdNr.: DE813185279
>> 
>> _______________________________________________
>> v6ops mailing list
>> v6ops@ietf.org
>> https://www.ietf.org/mailman/listinfo/v6ops
>