From owner-freebsd-hackers Tue Feb 24 17:54:50 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id RAA01495 for freebsd-hackers-outgoing; Tue, 24 Feb 1998 17:54:50 -0800 (PST) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from allegro.lemis.com (allegro.lemis.com [192.109.197.134]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id RAA01299 for ; Tue, 24 Feb 1998 17:54:27 -0800 (PST) (envelope-from grog@lemis.com) Received: from freebie.lemis.com (freebie.lemis.com [192.109.197.137]) by allegro.lemis.com (8.8.7/8.8.5) with ESMTP id MAA10423; Wed, 25 Feb 1998 12:24:13 +1030 (CST) Received: (from grog@localhost) by freebie.lemis.com (8.8.8/8.8.7) id MAA22908; Wed, 25 Feb 1998 12:24:12 +1030 (CST) (envelope-from grog) Message-ID: <19980225122411.62329@freebie.lemis.com> Date: Wed, 25 Feb 1998 12:24:11 +1030 From: Greg Lehey To: Chris Dillon , Adam Turoff Cc: hackers , Robert Glover Subject: Re: Token Ring for FreeBSD yet? References: <34F37C2A@smginc.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.89i In-Reply-To: ; from Chris Dillon on Tue, Feb 24, 1998 at 07:26:57PM -0600 WWW-Home-Page: http://www.lemis.com/~grog Organization: LEMIS, PO Box 460, Echunga SA 5153, Australia Phone: +61-8-8388-8286 Fax: +61-8-8388-8725 Mobile: +61-41-739-7062 Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Tue, 24 February 1998 at 19:26:57 -0600, Chris Dillon wrote: > > > On Tue, 24 Feb 1998, Adam Turoff wrote: > >> But...but...but... >> >> Token Ring is the most expensive, slowest networking protocol on the >> planet(*). Why wouldn't a slick, fast OS like FreeBSD support it? >> >> Realistically speaking, aren't there bridges that can translate >> Token Ring to Ethernet? If you're installing FreeBSD, it's stupid >> not to use Ethernet. The h/w is cheap and the OS support is solid. >> >> The other 99% of the computers on your LAN are the anomaly, not >> the ethernetted FreeBSD box. >> >> (*) SneakerNet is slower, but costs less. :-) > > I wouldn't exactly call Token Ring slow just because it is only running at > 4 or 16Mbit. Correct. There are other reasons to call it slow. > The 16Mbit Token Ring network could run circles around any 10Mbit > Ethernet network. I disagree strongly with this statement. > On a heavily congested network, even a 4Mbit Token Ring network > could outrun a 10Mbit Ethernet network, simply because of the > token-passing scheme that Token Ring uses. On a normal network, a 10Mbit Ethernet network could outrun a 16Mbit Token Ring network, simply because of the token-passing scheme that Token Ring uses. > CSMA/CD just isn't very efficient on a heavily loaded network. The > CSMA/CD network (Ethernet) would spend more time dealing with > collisions than it would passing usable data. Correct. But token passing isn't very efficient under any kind of load. > FDDI and Arcnet have the same advantages. So why are they both so popular? > There was even an 80Mbit Arcnet proposal at one time, which would > have been much better than Ethernet. Frankly, I would consider > Ethernet just above SneakerNet in the protocol arena, not the other > way around. :-) I did some theoretical calculations a while back to show the amount of overhead in CSMA/CD and in token passing. I've forgotten the details, and I can't find the calculations, but the token-passing overhead was much larger than you'd expect. It's rather like the difference between catching a train and taking a car. Ignoring the speed difference between cars and trains, the big problems are: - Cars can become very slow in traffic jams. Trains are not usually susceptible to traffic jams. - You have to wait for trains. Greg To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message