Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!husc6!bbn!uwmcsd1!ig!jade!saturn!eshop From: eshop@saturn.ucsc.edu (Jim Warner) Newsgroups: comp.dcom.lans Subject: Re: anyone out there with American Photonics RL-5000's? Message-ID: <1291@saturn.ucsc.edu> Date: Mon, 30-Nov-87 22:11:50 EST Article-I.D.: saturn.1291 Posted: Mon Nov 30 22:11:50 1987 Date-Received: Fri, 4-Dec-87 05:06:43 EST References: <209@yetti.UUCP> <19386@amdcad.AMD.COM> Reply-To: eshop@saturn.ucsc.edu (Jim Warner) Organization: University of California, Santa Cruz; CIS/CE Lines: 23 Keywords: API, fiber optics, 802.3, transceiver cable, RL-5000 In article <19386@amdcad.AMD.COM> phil@amdcad.UUCP (Phil Ngai) writes: >In article <209@yetti.UUCP> eriks@yetti.UUCP (Eriks Rugelis) writes: >>They call it a 'Fiber Optic Ethernet Expander'. > >.... First of all, the >heartbeat gets delayed. Second, your data echo gets delayed. Though >many pieces of equipment may work, who's to say someone won't design a >piece of equipment which knows that transceiver cables are never >longer than 50 meters? The problem of delayed data is occurs with broadband transceivers (Chipcom) and other fiber optic transceivers (Codenol) as well. In a broadband system, the signals must travel all the way to the head end before they are returned to the receiver section. There is definitely lots of equipment that will not tolerate this delay. These transceivers provide local (faked) echo. The Codenol rep told me there is a jumper internal to the transceiver to disable local echo, but there is never any reason to change it. I would be real suprised if the "Ethernet Expander" didn't do the same, but it is definitely a good question to ask. jim warner eshop@saturn.ucsc.edu