From owner-freebsd-hackers Sat Jun 20 04:22:38 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id EAA14646 for freebsd-hackers-outgoing; Sat, 20 Jun 1998 04:22:38 -0700 (PDT) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from awfulhak.org (awfulhak.force9.co.uk [195.166.136.63]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id EAA14641 for ; Sat, 20 Jun 1998 04:22:35 -0700 (PDT) (envelope-from brian@Awfulhak.org) Received: from gate.lan.awfulhak.org (localhost [127.0.0.1]) by awfulhak.org (8.8.8/8.8.8) with ESMTP id MAA01601; Sat, 20 Jun 1998 12:20:14 +0100 (BST) (envelope-from brian@gate.lan.awfulhak.org) Message-Id: <199806201120.MAA01601@awfulhak.org> X-Mailer: exmh version 2.0.1 12/23/97 To: bmah@CA.Sandia.GOV cc: Open Systems Networking , spork , Joel Ray Holveck , root@bmccane.maxbaud.net, hackers@FreeBSD.ORG Subject: Re: TweakDUN In-reply-to: Your message of "Sat, 20 Jun 1998 00:20:11 PDT." <199806200720.AAA24228@stennis.ca.sandia.gov> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Sat, 20 Jun 1998 12:20:14 +0100 From: Brian Somers Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > Ummm. Let me offer my corrections to this. According to some hurried math, a > 1500 byte packet takes about 520 ms to send via a 28.8Kbps link (assuming 10 > bits per byte due to stop/start bits, but not counting link-level framing). A > 576-byte packet is going to take about 200 ms. > > Where you *do* lose is the fact that for each of those packets, you have 40 > bytes of headers (20 IP + 20 TCP) that you can't lose for data. So you can > use 1460/1500 = 97% of the bytes in a packet for "real data", or 536/576 = 93% > of the bytes. (Again, discounting link-level framing overheads.) [.....] And turning on VJ compression just about negates this overhead. > Bruce. -- Brian , , Don't _EVER_ lose your sense of humour.... To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message