From owner-freebsd-hackers Wed Feb 25 17:31:24 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id RAA20843 for freebsd-hackers-outgoing; Wed, 25 Feb 1998 17:31:24 -0800 (PST) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from mailhost.onramp.net (mailhost.onramp.net [199.1.11.3]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id RAA20830 for ; Wed, 25 Feb 1998 17:31:00 -0800 (PST) (envelope-from dlittell@onramp.net) Received: from daze (ppp12-58.dllstx.onramp.net [206.50.200.186]) by mailhost.onramp.net (8.8.7/8.8.7) with SMTP id TAA24807 for ; Wed, 25 Feb 1998 19:30:58 -0600 (CST) Message-ID: <34F4C4ED.31DFF4F5@onramp.net> Date: Wed, 25 Feb 1998 19:27:09 -0600 From: Dave Littell Organization: Yeah, right..like we need this! X-Mailer: Mozilla 3.01 (X11; I; FreeBSD 2.1.6-RELEASE i386) MIME-Version: 1.0 To: hackers@FreeBSD.ORG Subject: Re: Token Ring for FreeBSD yet? References: <14181.888392839@verdi.nethelp.no> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG sthaug@nethelp.no wrote: > > > For example, can you guarantee, > > mathematically, that you can get a given mount of data across the network > > in a given amount of time, worst-case? Can't do that with Ethernet, since > > it works too chaotically. In token-passing and polling based networks, > > you can say with certainty that even under maximum load, you can get a > > packet from one machine to another in X milliseconds. > > Sorry, it's not that simple. On a token ring network, tokens can get lost. > Yes, this happens in real life. So any "guarantee" that you give for token > ring networks is based on statistics. > Yeah, it really is that simple. Token loss recovery time has an upper bound and token ring-based networks degrade gracefully, ensuring some non-zero throughput even at 100% offered load. I believe there are meltdown scenarios in Ethernet that guarantee you'll never get anything out. Dave To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message