Re: [mpls-tp] Fw: I-D Action:draft-ietf-mpls-tp-gach-dcn-06.txt
liu.guoman@zte.com.cn Tue, 22 September 2009 02:11 UTC
Return-Path: <liu.guoman@zte.com.cn>
X-Original-To: mpls-tp@core3.amsl.com
Delivered-To: mpls-tp@core3.amsl.com
Received: from localhost (localhost [127.0.0.1]) by core3.amsl.com (Postfix) with ESMTP id 65C5A3A6919 for <mpls-tp@core3.amsl.com>; Mon, 21 Sep 2009 19:11:43 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -97.19
X-Spam-Level:
X-Spam-Status: No, score=-97.19 tagged_above=-999 required=5 tests=[AWL=0.445, BAYES_00=-2.599, HTML_MESSAGE=0.001, MIME_BASE64_TEXT=1.753, MIME_CHARSET_FARAWAY=2.45, RCVD_DOUBLE_IP_LOOSE=0.76, USER_IN_WHITELIST=-100]
Received: from mail.ietf.org ([64.170.98.32]) by localhost (core3.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id fSoT3pmx5Rvh for <mpls-tp@core3.amsl.com>; Mon, 21 Sep 2009 19:11:42 -0700 (PDT)
Received: from mx6.zte.com.cn (mx6.zte.com.cn [63.218.89.70]) by core3.amsl.com (Postfix) with ESMTP id A50AE3A679F for <mpls-tp@ietf.org>; Mon, 21 Sep 2009 19:11:40 -0700 (PDT)
Received: from [10.30.17.99] by mx6.zte.com.cn with surfront esmtp id 9110764009499; Tue, 22 Sep 2009 09:54:57 +0800 (CST)
Received: from [10.30.3.18] by [10.30.17.99] with StormMail ESMTP id 79624.2706441429; Tue, 22 Sep 2009 10:01:22 +0800 (CST)
Received: from notes_smtp.zte.com.cn ([10.30.1.239]) by mse1.zte.com.cn with ESMTP id n8M2BOBq090363; Tue, 22 Sep 2009 10:11:25 +0800 (CST) (envelope-from liu.guoman@zte.com.cn)
In-Reply-To: <72071DDF03FE4940A892E28B4708C344@your029b8cecfe>
To: Adrian Farrel <adrian@olddog.co.uk>
MIME-Version: 1.0
X-Mailer: Lotus Notes Release 6.5.4 March 27, 2005
Message-ID: <OF8219F734.7BF3D584-ON48257639.0009BB7A-48257639.000BDD6C@zte.com.cn>
From: liu.guoman@zte.com.cn
Date: Tue, 22 Sep 2009 10:09:25 +0800
X-MIMETrack: Serialize by Router on notes_smtp/zte_ltd(Release 6.5.4|March 27, 2005) at 2009-09-22 10:11:18, Serialize complete at 2009-09-22 10:11:18
Content-Type: multipart/alternative; boundary="=_alternative 000BDD6948257639_="
X-MAIL: mse1.zte.com.cn n8M2BOBq090363
Cc: mpls-tp@ietf.org, ahtmpls@itu.int
Subject: Re: [mpls-tp] Fw: I-D Action:draft-ietf-mpls-tp-gach-dcn-06.txt
X-BeenThere: mpls-tp@ietf.org
X-Mailman-Version: 2.1.9
Precedence: list
List-Id: MPLS-TP Mailing list <mpls-tp.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/listinfo/mpls-tp>, <mailto:mpls-tp-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/mpls-tp>
List-Post: <mailto:mpls-tp@ietf.org>
List-Help: <mailto:mpls-tp-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/mpls-tp>, <mailto:mpls-tp-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 22 Sep 2009 02:11:43 -0000
Adrian thank you for replying quickly. your understanding to my problem is very true and your explaining is very precise. here I appreciate your answering. but I don't completely agree your opinions. specially, I don't accept your last section contents " However, if a use for TLVs is found in the future it is very easy to define new ACH Channel Types to represent "MCC with TLVs" and "SCC with TLVs." if it is easy to add new ACH Channel Types, it maybe unnecessary to need PID field in GACH message. we may use different ACH Channel Type value to indicate different type of MCC/SCC message. for example, we may use ACH Channel Type =1 to indicate IPv4/MCC, at the same time , we may use ACH Channel Type=2 to indicate IPv6/MCC. through this way, we may use ACH Channel Type (16bits) to indicate 2^16 Types of MCC/SCC Messages. why to add PID fields in the GACH messages? best regards liu "Adrian Farrel" <adrian@olddog.co.uk> 2009-09-21 18:51 请答复 给 "Adrian Farrel" <adrian@olddog.co.uk> 收件人 <liu.guoman@zte.com.cn> 抄送 <ahtmpls@itu.int>, <mpls-tp@ietf.org> 主题 Re: [mpls-tp] Fw: I-D Action:draft-ietf-mpls-tp-gach-dcn-06.txt Hello Liu, I think you are asking two questions. 1. Does draft-ietf-mpls-tp-gach-dcn change the format of the GACH, and if so how do we handle the change? 2. If there is no ACH TLV in the mcc/scc message, how will we extend the message if we need to? > according to the revison. maybe we revise > RFC5586? or else ,both drafts will have > different describles. > in additonal, if there is not any ACH TLV > in the mcc/scc message, how to extend > other functions in the future? or it must > be unnecessary to extend other functions > in the future for MCC/SCC message? To answer question 1, first... RFC 5586 defines that the GACH consist of: - ACh identifier (4 bits 0x1) - ACh version (4 bits 0x0) - Reserved (8 bits 0x0) - Channel Type (16 bits) - ACH TLV header (16 bits - OPTIONAL depending on Channel Type) - ACH TLVs (length depending on ACH TLV header, content depending on Channel Type) - G-ACh message. In draft-ietf-mpls-tp-gach-dcn we define as follows: - ACH TLV header is absent - ACH TLVs are absent - G-ACh message consists of: - PID (16 bits - PPP value) - MCC/SCC message I don't believe this changes the definition in RFC 5586 and nothing extra needs to be done. And now the second question. We have tried very hard to find any requirements to include TLVs in MCC/SCC G-ACh messages. We have failed to find any. If we include the ACH TLV header we could set the length to zero to indicate not TLVs. This would have the following disadvantages: - Every message would contain 4 unnecessary bytes - Every message would have to be parsed to check that the length was zero so increasing the processing. - If TLVs are present, implementations will not know how to process them. Given that we have no use for the TLVs, it seems best to avoid these issues. However, if a use for TLVs is found in the future it is very easy to define new ACH Channel Types to represent "MCC with TLVs" and "SCC with TLVs." Thanks, Adrian -------------------------------------------------------- ZTE Information Security Notice: The information contained in this mail is solely property of the sender's organization. This mail communication is confidential. Recipients named above are obligated to maintain secrecy and are not permitted to disclose the contents of this communication to others. This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the originator of the message. Any views expressed in this message are those of the individual sender. This message has been scanned for viruses and Spam by ZTE Anti-Spam system.
- [mpls-tp] Fw: I-D Action:draft-ietf-mpls-tp-gach-… Adrian Farrel
- Re: [mpls-tp] Fw: I-D Action:draft-ietf-mpls-tp-g… liu.guoman
- Re: [mpls-tp] Fw: I-D Action:draft-ietf-mpls-tp-g… Adrian Farrel
- Re: [mpls-tp] Fw: I-D Action:draft-ietf-mpls-tp-g… liu.guoman
- Re: [mpls-tp] Fw: I-D Action:draft-ietf-mpls-tp-g… Adrian Farrel