From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-32-ewr.dyndns.com (mxout-095-ewr.mailhop.org [216.146.33.95]) by lists.bufferbloat.net (Postfix) with ESMTP id 1265C2E0322 for ; Wed, 23 Mar 2011 08:13:19 -0700 (PDT) Received: from scan-32-ewr.mailhop.org (scan-32-ewr.local [10.0.141.238]) by mail-32-ewr.dyndns.com (Postfix) with ESMTP id 592386F6A92 for ; Wed, 23 Mar 2011 15:13:19 +0000 (UTC) X-Spam-Score: 0.0 () X-Mail-Handler: MailHop by DynDNS X-Originating-IP: 76.74.103.46 Received: from mail.vyatta.com (mail.vyatta.com [76.74.103.46]) by mail-32-ewr.dyndns.com (Postfix) with ESMTP id 1B2BA6FA623 for ; Wed, 23 Mar 2011 15:13:12 +0000 (UTC) Received: from localhost (localhost.localdomain [127.0.0.1]) by mail.vyatta.com (Postfix) with ESMTP id 540461829101 for ; Wed, 23 Mar 2011 08:13:11 -0700 (PDT) X-Virus-Scanned: amavisd-new at tahiti.vyatta.com Received: from mail.vyatta.com ([127.0.0.1]) by localhost (mail.vyatta.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id WvijUqpJwLpK for ; Wed, 23 Mar 2011 08:13:10 -0700 (PDT) Received: from nehalam (pool-74-107-135-205.ptldor.fios.verizon.net [74.107.135.205]) by mail.vyatta.com (Postfix) with ESMTPSA id 307DF18290F1 for ; Wed, 23 Mar 2011 08:13:10 -0700 (PDT) Date: Wed, 23 Mar 2011 08:13:08 -0700 From: Stephen Hemminger To: Bloat@lists.bufferbloat.net Message-ID: <20110323081308.10198612@nehalam> Organization: Vyatta X-Mailer: Claws Mail 3.7.6 (GTK+ 2.22.0; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: [Bloat] Fwd: Identifying TCP congestion control algorithms, and measurement results X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 23 Mar 2011 15:13:20 -0000 This showed up on the end-to-end mailing list and might be of interest to this group. It is interesting how many hosts are still using BIC (probably RHEL/Centos 5). BIC is known to be broken and unfair. From: Lisong Xu Date: Tue, Mar 15, 2011 at 3:36 PM Subject: [e2e] Identifying TCP congestion control algorithms, and measurement results Greetings, We have recently developed a tool, called TCP Congestion Control Avoidance Identification (CAAI), for actively identifying the TCP congestion avoidance algorithm of a remote web server. We used CAAI to measure the TCP algorithms of the top 5000 web sites in February 2011, and got some preliminary results in which you might be interested. # Only 16.85~25.58% of web servers still use the traditional AIMD. # 14.36%, 15.82%, and 14.33% of web servers use BIC, CUBIC' (kernel 2.6.25 and before), and CUBIC (kernel 2.6.26 and after), respectively. Total = 44.51%. # 9.97% and 0.30~9.03% of web servers use CTCP' (Windows Server 2003 and XP Pro x64) and CTCP (Windows Server 2008, Vista, and 7), respectively. Interestingly, CTCP' behaves very similar to HSTCP. Total = 10.27~19%. # Some web servers use non-default TCP algorithms (such as YEAH), some web servers use some unknown TCP algorithms which are not available in any major operating system family, and some web servers use abnormal slow start algorithms. More information is available at our project webpage http://cse.unl.edu/~xu/research/TCPcensus.html. Thanks Lisong -- Lisong Xu, Associate Professor Computer Science & Engineering University of Nebraska-Lincoln http://cse.unl.edu/~xu