IETF Logo Mail Archive

Re: [sfc] Doubt about draft-ietf-sfc-nsh-12

"Joel M. Halpern" <jmh@joelhalpern.com> Thu, 23 March 2017 15:24 UTC

Return-Path: <jmh@joelhalpern.com>
X-Original-To: sfc@ietfa.amsl.com
Delivered-To: sfc@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id A934312943C for <sfc@ietfa.amsl.com>; Thu, 23 Mar 2017 08:24:10 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2
X-Spam-Level:
X-Spam-Status: No, score=-2 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1024-bit key) header.d=joelhalpern.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 QSOGSpqLsFLS for <sfc@ietfa.amsl.com>; Thu, 23 Mar 2017 08:24:06 -0700 (PDT)
Received: from mailb2-alt.tigertech.net (mailb2-alt.tigertech.net [74.114.91.144]) (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 9F2BC1297CF for <sfc@ietf.org>; Thu, 23 Mar 2017 08:24:05 -0700 (PDT)
Received: from localhost (localhost [127.0.0.1]) by mailb2.tigertech.net (Postfix) with ESMTP id 5C6741C0CE3; Thu, 23 Mar 2017 08:24:05 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelhalpern.com; s=1.tigertech; t=1490282645; bh=414WpYcnNtNFXvN0OuV17u3QqUdc1uVW5Lrb/7hWTAI=; h=Subject:To:References:From:Date:In-Reply-To:From; b=kmN53akbyb1u32aIWKqHJjl9lgEM7MRylhw93Jzwe5+2M3ZosbagbzcWAXepOO762 OVPHOYsqyEJQbHhbIxaHmh+w0FIvBSJ/pWsaCd4e/Q+N1O61zWARxXTsIfwwl52r3w wK5EMH9h/u0IUZOqKb7DmhIWcpm5Y8huCMX7KjLo=
X-Virus-Scanned: Debian amavisd-new at b2.tigertech.net
Received: from Joels-MacBook-Pro.local (209-255-163-147.ip.mcleodusa.net [209.255.163.147]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mailb2.tigertech.net (Postfix) with ESMTPSA id BCB80521B49; Thu, 23 Mar 2017 08:24:04 -0700 (PDT)
To: "lizho.jin" <lizho.jin@gmail.com>, sfc <sfc@ietf.org>, paulq <paulq@cisco.com>, "uri.elzur" <uri.elzur@intel.com>
References: <0C4ABB6D-6E5F-4C87-8EF0-F8D7FF8C95A9@gmail.com>
From: "Joel M. Halpern" <jmh@joelhalpern.com>
Message-ID: <66bf1a04-d01a-e651-707f-f325edd9f0ef@joelhalpern.com>
Date: Thu, 23 Mar 2017 11:24:03 -0400
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.12; rv:45.0) Gecko/20100101 Thunderbird/45.8.0
MIME-Version: 1.0
In-Reply-To: <0C4ABB6D-6E5F-4C87-8EF0-F8D7FF8C95A9@gmail.com>
Content-Type: text/plain; charset="windows-1252"; format="flowed"
Content-Transfer-Encoding: 7bit
Archived-At: <https://mailarchive.ietf.org/arch/msg/sfc/p2gvobr2TEfFpRPogh4VZFMy1jI>
Subject: Re: [sfc] Doubt about draft-ietf-sfc-nsh-12
X-BeenThere: sfc@ietf.org
X-Mailman-Version: 2.1.22
Precedence: list
List-Id: Network Service Chaining <sfc.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/sfc>, <mailto:sfc-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/sfc/>
List-Post: <mailto:sfc@ietf.org>
List-Help: <mailto:sfc-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/sfc>, <mailto:sfc-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 23 Mar 2017 15:24:11 -0000

The content of the inner payload may change.  Lots of service functions 
change the content.  NAT, HTTP annotators, ...
THe semantics of the inner protocol (TCP is still TCP,...) remain the 
same.  if the semantics are changing, then the service function 
terminates one chain and starts another.

Yours,
Joel

On 3/23/17 11:15 AM, lizho.jin wrote:
> Hi Authors,
> I have a doubt with following description:
>
>    Next Protocol: indicates the protocol type of the encapsulated data.
>    NSH does not alter the inner payload, and the semantics on the inner
>    protocol remain unchanged due to NSH service function chaining.
>    Please see IANA Considerations section below.
>
> It says NSH does not alter the inner payload, but what if the SF is NAT,
>
> then the payload will be changed, right?
>
> Regards
>
> Lizhong
>
>
>
> _______________________________________________
> sfc mailing list
> sfc@ietf.org
> https://www.ietf.org/mailman/listinfo/sfc
>

v2.23.0 | Report a Bug | By Email