[rohc] Clarification required regarding the ECN_USED control filed in TCP Profile
Anil Maguluri <Anil.Maguluri@lntinfotech.com> Wed, 31 March 2010 04:48 UTC
Return-Path: <Anil.Maguluri@lntinfotech.com>
X-Original-To: rohc@core3.amsl.com
Delivered-To: rohc@core3.amsl.com
Received: from localhost (localhost [127.0.0.1]) by core3.amsl.com (Postfix) with ESMTP id E7EFE3A6935 for <rohc@core3.amsl.com>; Tue, 30 Mar 2010 21:48:07 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.772
X-Spam-Level:
X-Spam-Status: No, score=-2.772 tagged_above=-999 required=5 tests=[AWL=1.300, BAYES_00=-2.599, DNS_FROM_OPENWHOIS=1.13, HTML_MESSAGE=0.001, MIME_QP_LONG_LINE=1.396, RCVD_IN_DNSWL_MED=-4]
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 lgfnsnGz8mQD for <rohc@core3.amsl.com>; Tue, 30 Mar 2010 21:48:06 -0700 (PDT)
Received: from mail96.messagelabs.com (mail96.messagelabs.com [216.82.254.19]) by core3.amsl.com (Postfix) with ESMTP id A4CA33A682D for <rohc@ietf.org>; Tue, 30 Mar 2010 21:48:06 -0700 (PDT)
X-VirusChecked: Checked
X-Env-Sender: Anil.Maguluri@lntinfotech.com
X-Msg-Ref: server-10.tower-96.messagelabs.com!1270010384!51428039!11
X-StarScan-Version: 6.2.4; banners=lntinfotech.com,-,-
X-Originating-IP: [203.101.96.8]
Received: (qmail 4585 invoked from network); 31 Mar 2010 04:48:34 -0000
Received: from unknown (HELO BLRINMSHTCAS02.bglrodc.lntinfotech.com) (203.101.96.8) by server-10.tower-96.messagelabs.com with AES128-SHA encrypted SMTP; 31 Mar 2010 04:48:34 -0000
Received: from blrinmsmbx01.bglrodc.lntinfotech.com ([169.254.1.247]) by BLRINMSHTCAS02.bglrodc.lntinfotech.com ([172.28.0.83]) with mapi; Wed, 31 Mar 2010 10:13:04 +0530
From: Anil Maguluri <Anil.Maguluri@lntinfotech.com>
To: "rohc@ietf.org" <rohc@ietf.org>
Date: Wed, 31 Mar 2010 10:12:57 +0530
Thread-Topic: Clarification required regarding the ECN_USED control filed in TCP Profile
Thread-Index: AcrQjKJudqQC4Am8RhGKD2NHikl9TQ==
Message-ID: <C7232BDB534C6241BE85C96D129205D002F41D1E10@BLRINMSMBX01.bglrodc.lntinfotech.com>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
acceptlanguage: en-US
Content-Type: multipart/alternative; boundary="_000_C7232BDB534C6241BE85C96D129205D002F41D1E10BLRINMSMBX01b_"
MIME-Version: 1.0
Cc: Anil Maguluri <Anil.Maguluri@lntinfotech.com>, Anil Kumar Maguluri <anilmaguluri@gmail.com>
Subject: [rohc] Clarification required regarding the ECN_USED control filed in TCP Profile
X-BeenThere: rohc@ietf.org
X-Mailman-Version: 2.1.9
Precedence: list
List-Id: Robust Header Compression <rohc.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/listinfo/rohc>, <mailto:rohc-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/rohc>
List-Post: <mailto:rohc@ietf.org>
List-Help: <mailto:rohc-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/rohc>, <mailto:rohc-request@ietf.org?subject=subscribe>
X-List-Received-Date: Wed, 31 Mar 2010 04:48:08 -0000
Hi All, Please clarify me whether my understanding is right or not. As per my understanding, the ecn_used flag is enable whenever the TCP SYN packet has ECE and CWR bits are set (ENC-SETUP SYN). This information is going to send using TCP dynamic chain (tcp_ecn_flags) and set ecn_used flag in the TCP Dynamic chain in the IR packet. Decompressor receives the IR packet with ecn_used flag is set, update the ecn_used flag in the context. Whenever ecn_used flag is enable, compressor has to send TCP/IP ECN flags in the irregular chain of the compressed packets and decompressor has to decode it from the irregular chain to reconstruct the packet. Please clarify the below queries. è If the TCP flow started with ECN enable/supported, is it static the life time of the flow? è If not, is TCP is going to send SYN packet again with disabling the ECE and CWR flags? è How frequently TCP flow can change from ECN enable to non-ECN? è If the TCP flow is changed from ECN capable to non-ECN, compressor has to inform to decompressor while setting the ecn_used as zero. Right? So that, compressor no need to sending TCP/IP ECN flags in the irregular chain. Thanks for your support. Regards, Anil Kumar Maguluri ________________________________ This Email may contain confidential or privileged information for the intended recipient (s) If you are not the intended recipient, please do not use or disseminate the information, notify the sender and delete it from your system. ______________________________________________________________________
- [rohc] Clarification required regarding the ECN_U… Anil Maguluri