IETF Logo Mail Archive

Re: SRH insertion vs encapsulation (Re: Next steps on Extension Header Insertion)

"Stefano Previdi (sprevidi)" <sprevidi@cisco.com> Fri, 04 November 2016 17:01 UTC

Return-Path: <sprevidi@cisco.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 2A1AB1295D8 for <ipv6@ietfa.amsl.com>; Fri, 4 Nov 2016 10:01:25 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -16.018
X-Spam-Level:
X-Spam-Status: No, score=-16.018 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, RCVD_IN_MSPIKE_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, RP_MATCHES_RCVD=-1.497, SPF_PASS=-0.001, USER_IN_DEF_DKIM_WL=-7.5] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1024-bit key) header.d=cisco.com
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 fyeheTopXxVW for <ipv6@ietfa.amsl.com>; Fri, 4 Nov 2016 10:01:22 -0700 (PDT)
Received: from rcdn-iport-4.cisco.com (rcdn-iport-4.cisco.com [173.37.86.75]) (using TLSv1.2 with cipher DHE-RSA-SEED-SHA (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 3A8E51295DC for <ipv6@ietf.org>; Fri, 4 Nov 2016 10:01:21 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=cisco.com; i=@cisco.com; l=2120; q=dns/txt; s=iport; t=1478278881; x=1479488481; h=from:to:cc:subject:date:message-id:references: in-reply-to:content-id:content-transfer-encoding: mime-version; bh=aTDI26R72km4TKmklBUf5CLYoBwyDAqxkY1KsVf4wc4=; b=JvL2Al4kFPF/ZajGH2QNrv8/ICKdgc5YV3JcfLMuePEikTYmZw63QDzH g3Xh5gdJcZBCg+7lKkXRw/nq3Q2tC+UdHocgyMTAbmCUNS9MXG3yN3+1q laamwHcWyomDWAor6tDnSgwTawQjGNkbe3iS7nY3tCdL0yYmNXvvpDVyE 0=;
X-IronPort-Anti-Spam-Filtered: true
X-IronPort-Anti-Spam-Result: A0AYAQAxvhxY/5xdJa1dGQEBAQEBAQEBAQEBBwEBAQEBgy4BAQEBAR9YfAeNMZcAgxGRNYIIHQuFewIagXw/FAECAQEBAQEBAWIohGEBAQEDAQEBASAROgsFCwIBBgIYAgImAgICJQsVEAIEDgWIUAgOkVOdP4x1AQEBAQEBAQEBAQEBAQEBAQEBAQEBFwWBCYU2gX2CWIQqAQEyI4JKLYIvAQSIS5FYAZA/kAqNIYQDAR43bINcgUVyAYUWgSGBDAEBAQ
X-IronPort-AV: E=Sophos;i="5.31,444,1473120000"; d="scan'208";a="167501686"
Received: from rcdn-core-5.cisco.com ([173.37.93.156]) by rcdn-iport-4.cisco.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 04 Nov 2016 17:01:20 +0000
Received: from XCH-RTP-010.cisco.com (xch-rtp-010.cisco.com [64.101.220.150]) by rcdn-core-5.cisco.com (8.14.5/8.14.5) with ESMTP id uA4H1Kv1014837 (version=TLSv1/SSLv3 cipher=AES256-SHA bits=256 verify=FAIL); Fri, 4 Nov 2016 17:01:20 GMT
Received: from xch-rtp-010.cisco.com (64.101.220.150) by XCH-RTP-010.cisco.com (64.101.220.150) with Microsoft SMTP Server (TLS) id 15.0.1210.3; Fri, 4 Nov 2016 13:01:19 -0400
Received: from xch-rtp-010.cisco.com ([64.101.220.150]) by XCH-RTP-010.cisco.com ([64.101.220.150]) with mapi id 15.00.1210.000; Fri, 4 Nov 2016 13:01:19 -0400
From: "Stefano Previdi (sprevidi)" <sprevidi@cisco.com>
To: 神明達哉 <jinmei@wide.ad.jp>
Subject: Re: SRH insertion vs encapsulation (Re: Next steps on Extension Header Insertion)
Thread-Topic: SRH insertion vs encapsulation (Re: Next steps on Extension Header Insertion)
Thread-Index: AQHSNr0QKS701bo2X0uW3hP4BwNirA==
Date: Fri, 04 Nov 2016 17:01:19 +0000
Message-ID: <C4DBE2C0-FEFB-4D33-8B9F-F19807AF6E11@cisco.com>
References: <CAJE_bqebnwwDj_00=N-ZNffE++SaEMwA6vT+i-nb0C_vmZHCRA@mail.gmail.com>
In-Reply-To: <CAJE_bqebnwwDj_00=N-ZNffE++SaEMwA6vT+i-nb0C_vmZHCRA@mail.gmail.com>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
x-ms-exchange-messagesentrepresentingtype: 1
x-ms-exchange-transport-fromentityheader: Hosted
x-originating-ip: [10.61.106.237]
Content-Type: text/plain; charset="utf-8"
Content-ID: <952AEFB66DC0A6438A955B78DFDC63FC@emea.cisco.com>
Content-Transfer-Encoding: base64
MIME-Version: 1.0
Archived-At: <https://mailarchive.ietf.org/arch/msg/ipv6/aClTsFuxn5cfVvDIbhf4XsZiFww>
Cc: Fernando Gont <fgont@si6networks.com>, 6man WG <ipv6@ietf.org>, Bob Hinden <bob.hinden@gmail.com>
X-BeenThere: ipv6@ietf.org
X-Mailman-Version: 2.1.17
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: <https://mailarchive.ietf.org/arch/browse/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: Fri, 04 Nov 2016 17:01:25 -0000

> On Nov 4, 2016, at 5:03 PM, 神明達哉 <jinmei@wide.ad.jp> wrote:
> 
> At Fri, 4 Nov 2016 11:16:34 +0000,
> Tim Chown <Tim.Chown@jisc.ac.uk> wrote:
> 
>>> Huh? The segment routing header is far from imaginary.
>> 
>> But what do you deduce is really being specified in the SRH drafts?
>> 
>> In draft-ietf-6man-segment-routing-header-02 it says in section 2.2:
>> [...]
>> which implies the SRH uses encapsulation, and doesn’t insert an EH
>> in the existing header chain.
> 
> My understanding is that actual implementations don't follow what's
> written in the draft and do insert an SRH:
> https://www.ietf.org/mail-archive/web/ipv6/current/msg24236.html


In fact, there are implementations that do what’s written in the draft and also do header insertion for some use cases. The use cases applies to controlled environments where, typically, a EH is inserted at ingress and removed at egress. This is the reality of v6 segment routing implementations used over v6 infrastructure of some operators.

s.



> (And my understanding is that the desire of some people to make the
> "actual" behavior explicitly standard-compliant is one major
> background motivation of why we are having this thread.)

> 
> --
> JINMEI, Tatuya
> 
> --------------------------------------------------------------------
> IETF IPv6 working group mailing list
> ipv6@ietf.org
> Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6
> --------------------------------------------------------------------

v2.23.0 | Report a Bug | By Email