IETF Logo Mail Archive

Re: [CCAMP] One comment on draft-zhang-ccamp-flexible-grid-ospf-ext

Jonas Mårtensson <Jonas.Martensson@acreo.se> Wed, 30 April 2014 09:28 UTC

Return-Path: <Jonas.Martensson@acreo.se>
X-Original-To: ccamp@ietfa.amsl.com
Delivered-To: ccamp@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 8D5991A6F34 for <ccamp@ietfa.amsl.com>; Wed, 30 Apr 2014 02:28:10 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.599
X-Spam-Level:
X-Spam-Status: No, score=-1.599 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, HTML_MESSAGE=0.001, MIME_8BIT_HEADER=0.3, RCVD_IN_DNSWL_NONE=-0.0001] 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 RLw7wTPJ24ir for <ccamp@ietfa.amsl.com>; Wed, 30 Apr 2014 02:28:08 -0700 (PDT)
Received: from smtp12-outgoing.stejtech.net (smtp12.stejtech.net [83.140.31.185]) by ietfa.amsl.com (Postfix) with ESMTP id 5CC4A1A6F25 for <ccamp@ietf.org>; Wed, 30 Apr 2014 02:28:08 -0700 (PDT)
X-Spam-STAY-ID: v=2.0 cv=frlelSEf c=1 sm=0 a=fpfCo9GHTwTpwwPQDU8l2g==:17 a=Bghysmw7pYwA:10 a=K1w0Dd5vJuUA:10 a=xqWC_Br6kY4A:10 a=48vgC7mUAAAA:8 a=AUd_NHdVAAAA:8 a=1RTuLK3dAAAA:8 a=k-bbf7aCikbaDoeD4e4A:9 a=QEXdDO2ut3YA:10 a=lZB815dzVvQA:10 a=JfD0Fch1gWkA:10 a=ZbphizX4KjIA:10 a=3Lu139M1AF5D5OFa:21 a=bmtdxOiD93CKPPjK:21 a=yMhMjlubAAAA:8 a=SSmOFEACAAAA:8 a=tJxKWT4cyQXgwpXWoeAA:9 a=gKO2Hq4RSVkA:10 a=UiCQ7L4-1S4A:10 a=hTZeC7Yk6K0A:10 a=frz4AuCg-hUA:10 a=zeWU4cnarEdtpr-x:21 a=SyV4l8zzBXVvrsox:21
Received: from mail.acreo.se (unknown [217.151.196.13]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) by smtp12.stejtech.net (Postfix) with ESMTPSA id 8AD5BBD0196; Wed, 30 Apr 2014 11:28:05 +0200 (CEST)
Received: from ACREOEXC02.ad.acreo.se ([::1]) by ACREOEXC02.ad.acreo.se ([::1]) with mapi id 14.03.0158.001; Wed, 30 Apr 2014 11:28:05 +0200
From: Jonas Mårtensson <Jonas.Martensson@acreo.se>
To: Ramon Casellas <ramon.casellas@cttc.es>, "ccamp@ietf.org" <ccamp@ietf.org>
Thread-Topic: [CCAMP] One comment on draft-zhang-ccamp-flexible-grid-ospf-ext
Thread-Index: AQHPZEe7nuP11G99nUmrjuo/ceEnxZsptIeAgAAGnYCAACLpcA==
Date: Wed, 30 Apr 2014 09:28:03 +0000
Message-ID: <7ECED07E132D4B4F89DCC0FDA683C6C25166A9@ACREOEXC02.ad.acreo.se>
References: <OF0A598851.0C5441D6-ON48257CCA.00242580-48257CCA.00279CC7@zte.com.cn> <CF8674F4.5E1E3%ggalimbe@cisco.com> <C636AF2FA540124E9B9ACB5A6BECCE6B302264D7@SZXEMA512-MBS.china.huawei.com> <5360BBA5.3070804@cttc.es>
In-Reply-To: <5360BBA5.3070804@cttc.es>
Accept-Language: en-US, sv-SE
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
x-originating-ip: [10.4.144.101]
Content-Type: multipart/alternative; boundary="_000_7ECED07E132D4B4F89DCC0FDA683C6C25166A9ACREOEXC02adacreo_"
MIME-Version: 1.0
Archived-At: http://mailarchive.ietf.org/arch/msg/ccamp/Vs-Hji2NgcYU6ya7jMY7DyEQjIU
Subject: Re: [CCAMP] One comment on draft-zhang-ccamp-flexible-grid-ospf-ext
X-BeenThere: ccamp@ietf.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: Discussion list for the CCAMP working group <ccamp.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ccamp>, <mailto:ccamp-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/ccamp/>
List-Post: <mailto:ccamp@ietf.org>
List-Help: <mailto:ccamp-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ccamp>, <mailto:ccamp-request@ietf.org?subject=subscribe>
X-List-Received-Date: Wed, 30 Apr 2014 09:28:10 -0000

Hi Ramon,

I don’t have a strong opinion either but isn’t the definition of the Port Label Restriction sub-TLV a separate issue from the future-proofing of the flexible grid label encoding? I mean the purpose of this sub-TLV is to describe a port on a switch that supports only a restricted subset of the full flexible grid.

Isn’t there a possibility that a particular switch could be restricted to granularities not following the 2:1 relationship due to some technology limitation?

/Jonas

From: CCAMP [mailto:ccamp-bounces@ietf.org] On Behalf Of Ramon Casellas
Sent: den 30 april 2014 11:00
To: ccamp@ietf.org
Subject: Re: [CCAMP] One comment on draft-zhang-ccamp-flexible-grid-ospf-ext

El 30/04/2014 10:36, Zhangxian (Xian) escribió:
Hi, Lei, Gabriele,

  Thank you for the comments. Please see my reply inline:

From: Gabriele Maria Galimberti (ggalimbe) [mailto:ggalimbe@cisco.com]
Sent: 2014年4月30日 15:42
To: wang.lei131@zte.com.cn<mailto:wang.lei131@zte.com.cn>; ccamp@ietf.org<mailto:ccamp@ietf.org>; Zhangxian (Xian)
Subject: Re: [CCAMP] One comment on draft-zhang-ccamp-flexible-grid-ospf-ext

I agree with LeWang,

Xian:  I think Lei has made a good point, i.e., CFG and SWG currently has a fixed relationship.  Will remove one field (i.e., CFG) to avoid carrying duplicated information in the next rotation of the draft. If anyone has different opinions, please speak up.

Ramon> I don't know, I don't have a strong opinion, yet if we check

https://datatracker.ietf.org/documents/LIAISON/liaison-2014-04-23-itu-t-sg-15-ccamp-lsr-on-flexible-grid-reply-to-ietf-ccamp-ls012-attachment-1.pdf

quote
"If such a proposal is made in the future, it is more likely that a second flexible grid with different granularity will be defined in addition to the existing grid rather than changes made to the current flexible grid (...) One of the reasons behind the 2:1 relationship between the slot width granularity and the nominal
central frequency granularity in the current flexible grid is to be able to describe any of the existing fixed spacing grids in Recommendation ITU-T G.694.1 using the flexible grid. If in future a flexible grid with finer granularity is introduced, the same 2:1 relationship should not be assumed."

so it is a design trade-off? do we stick to the current grid definition *only* or we are more future-proof?

Ramon

v2.23.0 | Report a Bug | By Email