From owner-freebsd-net Thu Jul 1 14:16:47 1999 Delivered-To: freebsd-net@freebsd.org Received: from sumatra.americantv.com (sumatra.americantv.com [208.139.222.227]) by hub.freebsd.org (Postfix) with ESMTP id 33D3D150C4 for ; Thu, 1 Jul 1999 14:16:42 -0700 (PDT) (envelope-from jlemon@americantv.com) Received: from right.PCS (right.PCS [148.105.10.31]) by sumatra.americantv.com (8.8.5/8.8.5) with ESMTP id QAA20234; Thu, 1 Jul 1999 16:16:41 -0500 (CDT) Received: (from jlemon@localhost) by right.PCS (8.6.13/8.6.4) id QAA04701; Thu, 1 Jul 1999 16:16:40 -0500 Message-ID: <19990701161639.29611@right.PCS> Date: Thu, 1 Jul 1999 16:16:39 -0500 From: Jonathan Lemon To: bmah@CA.Sandia.GOV Cc: net@FreeBSD.ORG Subject: Re: Slow start? References: <19990701134131.58921@right.PCS> <199907012101.OAA05102@stennis.ca.sandia.gov> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.61.1 In-Reply-To: <199907012101.OAA05102@stennis.ca.sandia.gov>; from Bruce A. Mah on Jul 07, 1999 at 02:01:42PM -0700 Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Jul 07, 1999 at 02:01:42PM -0700, Bruce A. Mah wrote: > If memory serves me right, Jonathan Lemon wrote: > > > I'm slightly confused; is slow-start still required if both hosts > > are on the same "LAN"? Note that a bridged environment is still > > considered a single LAN for ethernet purposes, even though the hosts > > may be separated by (say) an ISDN bridge. > > For a host sending to another host on the same *subnet*, no, the sender > doesn't go through slow-start. (In BSD-derived TCP stacks.) > > "Another host on the same subnet" means that the sender doesn't need to > forward packets through a router to get to the destination, which is a > slightly broader case than "the same 'LAN'". Yeah, digging around, I just found the relevant subroutine: in_localaddr(). I was suprised, since I expected slow start in all cases. While I can understand why slow start may not be desirable on a "local subnet", some of this code seems dated. I mean, it still calculates the netmask as CLASS_A(), CLASS_B(), etc. -- Jonathan To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message