From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nanda Kumar Subject: Re: Default TCP Options creating problems Date: Fri, 27 Jan 2012 21:21:54 +0530 Message-ID: <4F22C81A.8090800@gmail.com> References: <4F22B17A.2080809@gmail.com> <1327675774.2220.13.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: netdev@vger.kernel.org, davem@davemloft.net To: Eric Dumazet Return-path: Received: from mail-iy0-f174.google.com ([209.85.210.174]:60913 "EHLO mail-iy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751994Ab2A0PLS (ORCPT ); Fri, 27 Jan 2012 10:11:18 -0500 Received: by iacb35 with SMTP id b35so2152505iac.19 for ; Fri, 27 Jan 2012 07:11:17 -0800 (PST) In-Reply-To: <1327675774.2220.13.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC> Sender: netdev-owner@vger.kernel.org List-ID: Hi Eric, On Friday 27 January 2012 08:19 PM, Eric Dumazet wrote: > Le vendredi 27 janvier 2012 =C3=A0 19:45 +0530, Nanda Kumar a =C3=A9c= rit : >> Hi, >> >> I am using Ubuntu 11.10 and unable to connect to my ISP login server= =2E >> The same is working under windows. Under linux, ISP server does not >> respond TCP SYN packet even. I did a comparison of packet capture of >> windows and linux and found, linux include TCP options by default. >> After manually disabling TCP Timestamp via sysctl, the login is >> happening fine. >> >> Is there any reason why TCP option is enabled by default? The same >> problem was happening under OpenSUSE 12.1 x86_64 also. My friend >> informed me that his android mobile is also unable to connect to ISP >> login server. > I am very sorry, but you should complain to your ISP, 20 years after = RFC > 1323, it should support it. > > TCP options are ... options, and as such should not be denied by a > conformant TCP stack. > > > > Thank you for the reply. Yes even I feel so. I have put up this issue t= o=20 ISP. However this issue is happening only with TCP timestamp option. All=20 other options are working fine. Any idea? Regards, Nandakumar