Re: [mpls] draft-fang-mpls-label-forwarding-no-swap - how much does it really save?

Robert Raszuk <robert@raszuk.net> Fri, 24 July 2015 16:05 UTC

Return-Path: <rraszuk@gmail.com>
X-Original-To: mpls@ietfa.amsl.com
Delivered-To: mpls@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 106EF1A87C0 for <mpls@ietfa.amsl.com>; Fri, 24 Jul 2015 09:05:50 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -0.677
X-Spam-Level:
X-Spam-Status: No, score=-0.677 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, FM_FORGED_GMAIL=0.622, FREEMAIL_FROM=0.001, HTML_MESSAGE=0.001, J_CHICKENPOX_42=0.6, SPF_PASS=-0.001] autolearn=no
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 AhD753k2PSKR for <mpls@ietfa.amsl.com>; Fri, 24 Jul 2015 09:05:48 -0700 (PDT)
Received: from mail-wi0-x235.google.com (mail-wi0-x235.google.com [IPv6:2a00:1450:400c:c05::235]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 222391A8726 for <mpls@ietf.org>; Fri, 24 Jul 2015 09:05:48 -0700 (PDT)
Received: by wicgb10 with SMTP id gb10so35190769wic.1 for <mpls@ietf.org>; Fri, 24 Jul 2015 09:05:46 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date:message-id:subject :from:to:cc:content-type; bh=jdIfk0KNIXDmY+tevfGYS4lEufxnpY7xGY+sQ9JweEo=; b=UwcE6ovzLN8DYKTCFxDCXJlto2iGgZvQfElAFwUIkDQp2XGvUiXgKCQzs+8EOGAqZ4 u9WLoLdyH7aLq9cDsgwCTs47Yo0gkF3TVljpCO9u7IdicDijhceRJQBLycAR4TWII9v5 xK2JwmZCqld+SHeTi55B5ab1RVceFjlS8WRZk4RB7NWmgQ5aDuZwSwe5gF1FiakmEf8A OP5nvtsVXVkqokLYVM+aklmKI+/RYgqBqB+Xo0GTagBn4IVE6RjnHGazbbfGrCEr410c LsyEiBziGUdsG+SylUa+ehQpXs2v5wjq60gdAXDJewoPo+IMwWwd6hYt41YZzY+HuLq8 wJbQ==
MIME-Version: 1.0
X-Received: by 10.181.13.195 with SMTP id fa3mr8671038wid.7.1437753946741; Fri, 24 Jul 2015 09:05:46 -0700 (PDT)
Sender: rraszuk@gmail.com
Received: by 10.194.95.168 with HTTP; Fri, 24 Jul 2015 09:05:46 -0700 (PDT)
Received: by 10.194.95.168 with HTTP; Fri, 24 Jul 2015 09:05:46 -0700 (PDT)
In-Reply-To: <5365D2B8-E3A1-4C25-85B4-C82CDE03090B@ericsson.com>
References: <DB3PR03MB078098C91E8D3C7DCDCCF8C39D840@DB3PR03MB0780.eurprd03.prod.outlook.com> <EA360A7AB9D90D4B9E9173B6D27C371EE3F6038F@MTKMBS61N1.mediatek.inc> <55B11D6D.2040102@pi.nu> <EA360A7AB9D90D4B9E9173B6D27C371EE3F607FB@MTKMBS61N1.mediatek.inc> <55B2552A.80702@juniper.net> <5365D2B8-E3A1-4C25-85B4-C82CDE03090B@ericsson.com>
Date: Fri, 24 Jul 2015 18:05:46 +0200
X-Google-Sender-Auth: eULxRVeMVyA-OxXEZxKvTC5Gzlg
Message-ID: <CA+b+ERm5Ap=EF5CMBcgsyczfqkpBD+34ChSekD1xXw+JRvxGgA@mail.gmail.com>
From: Robert Raszuk <robert@raszuk.net>
To: Jeff Tantsura <jeff.tantsura@ericsson.com>
Content-Type: multipart/alternative; boundary=f46d043c07d44524d2051ba12dbb
Archived-At: <http://mailarchive.ietf.org/arch/msg/mpls/AmdksQDGP-2EeOinO_lTkJG0vdc>
Cc: mpls@ietf.org
Subject: Re: [mpls] draft-fang-mpls-label-forwarding-no-swap - how much does it really save?
X-BeenThere: mpls@ietf.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: Multi-Protocol Label Switching WG <mpls.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/mpls>, <mailto:mpls-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/mpls/>
List-Post: <mailto:mpls@ietf.org>
List-Help: <mailto:mpls-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/mpls>, <mailto:mpls-request@ietf.org?subject=subscribe>
X-List-Received-Date: Fri, 24 Jul 2015 16:05:50 -0000

I always thought that #1 is "Money talks" ;).

And with that why don't we define NO_SWAP as experimental RFC and let the
market decide how useful it will be ?

If say after few years it will have zero adoption its pretty simple to move
it to historical status and consider experiment as concluded.

Best,
R.
On Jul 24, 2015 5:24 PM, "Jeff Tantsura" <jeff.tantsura@ericsson.com> wrote:

> Experience talks ;-)
>
> Would be really great to get quantification.
>
> Regards,
> Jeff
>
> On Jul 24, 2015, at 5:09 PM, Eric C Rosen <erosen@juniper.net> wrote:
>
> >> When standard defines a "no-swap" operation,  ASIC engineer would
> >> implement such operation completely differently
> >
> > Well, this is where we came in.  The RFCs do not dictate how the ASICs
> > should be designed, and your ASIC designers are free to design in
> > whatever way best meets the needs of the systems that are going to use
> > those ASICs.  You can put in any optimizations you think are warranted.
> If you expect the ASICs to be used in products that will never need to swap
> label values, never need to push labels, never need to pop labels, then you
> are free to design the ASICs without any of these features.  If you think
> that these operations are needed, but that "don't change the label value or
> the stack size" are the most common operations, you can certainly optimize
> your design for that case.
> >
> > But if you think you can get the ASICs designed properly simply by
> handing the RFCs to the ASIC designers, you may be in for an unpleasant
> surprise.
> >
> >> Since the label is to be "swap"ed with a new LABEL stack, then the
> >> design of SWAPPING need to consider TTL handling such as 1) just
> >> decrement of original TTL or 2) using a brand new TTL, such as using
> >> local new register stored value to Fill the sawp'ed new label stack.
> >
> > The TTL handling is exactly the same for both cases.  If you have been
> telling your ASIC designers something different, you most definitely are in
> for an unpleasant surprise.
> >
> >
> >
> >
> >
> >
> > _______________________________________________
> > mpls mailing list
> > mpls@ietf.org
> > https://www.ietf.org/mailman/listinfo/mpls
>
> _______________________________________________
> mpls mailing list
> mpls@ietf.org
> https://www.ietf.org/mailman/listinfo/mpls
>