From owner-freebsd-net@FreeBSD.ORG Thu Apr 12 14:28:02 2007 Return-Path: X-Original-To: freebsd-net@freebsd.org Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id B8FD116A400; Thu, 12 Apr 2007 14:28:02 +0000 (UTC) (envelope-from mallman@icir.org) Received: from pork.ICSI.Berkeley.EDU (pork.ICSI.Berkeley.EDU [192.150.186.19]) by mx1.freebsd.org (Postfix) with ESMTP id 953DD13C44C; Thu, 12 Apr 2007 14:28:02 +0000 (UTC) (envelope-from mallman@icir.org) Received: from guns.icir.org (adsl-69-222-35-58.dsl.bcvloh.ameritech.net [69.222.35.58]) by pork.ICSI.Berkeley.EDU (8.12.11.20060308/8.12.11) with ESMTP id l3CDScVG010048; Thu, 12 Apr 2007 06:28:39 -0700 Received: from lawyers.icir.org (adsl-69-222-35-58.dsl.bcvloh.ameritech.net [69.222.35.58]) by guns.icir.org (Postfix) with ESMTP id 6BF819CA538; Thu, 12 Apr 2007 09:28:33 -0400 (EDT) Received: from lawyers.icir.org (localhost [127.0.0.1]) by lawyers.icir.org (Postfix) with ESMTP id 3196B1CF21E; Thu, 12 Apr 2007 09:28:21 -0400 (EDT) To: LI Xin From: Mark Allman In-Reply-To: <461DFB2B.10106@delphij.net> Organization: ICSI Center for Internet Research (ICIR) Song-of-the-Day: Blue on Black MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=_bOundary"; micalg=pgp-sha1; protocol="application/pgp-signature" Date: Thu, 12 Apr 2007 09:28:21 -0400 Sender: mallman@icir.org Message-Id: <20070412132821.3196B1CF21E@lawyers.icir.org> Cc: freebsd-net@freebsd.org, "Bruce M. Simpson" Subject: Re: [PATCH] kern/681110 re-roll of RFC3522 (Eifel detection) patchset X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: mallman@icir.org List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 12 Apr 2007 14:28:02 -0000 --=_bOundary Content-Type: text/plain; charset=us-ascii Content-Disposition: inline > BTW. Is there any legal alternative, e.g. make this as an option like > WANT_IDEA? I do not know what WANT_IDEA is. As far as alternatives, there is F-RTO (RFC 4138) and DSACK (RFCs 2883 & 3708). We have also worked on a response that is different (and unencumbered). It is just an internet-draft (and, in fact, needs rev-ed because we have a better idea in mind): Josh Blanton, Ethan Blanton, Mark Allman. Using Spurious Retransmissions to Adapt the Retransmission Timeout. December 2006. Internet-Draft draft-allman-rto-backoff-04.txt (work in progress). The problem is that these are not technically as good as Eifel, IMO. But, Ericsson has taken the obvious way to do things off the table, I am afraid. (Lots of the Eifel work would seem to me to not stand up to a challenge based on previous/simultaneous work and the obviousness of it. But, that is clearly pure conjecture and I am not putting up the funds to test the theory.) The good news is that in most environments if you use the standard RTO timer (RFC 2988) then the number of spurious timeouts experienced is vanishingly small. See: Mark Allman, Vern Paxson. On Estimating End-to-End Network Path Properties. Proceedings of the ACM SIGCOMM Technical Symposium, Cambridge, MA, September 1999. http://www.icir.org/mallman/papers/estimation.ps allman --=_bOundary Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (Darwin) iD8DBQFGHjP1WyrrWs4yIs4RAnKgAJwIlFn4NbC3Jucs7b2KT6QihT7jLQCfXUXA MBr3TUIE7VzCkm37tXUhf8o= =uCEJ -----END PGP SIGNATURE----- --=_bOundary--