Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!husc6!cfa!wyatt From: wyatt@cfa.harvard.EDU (Bill Wyatt) Newsgroups: comp.os.vms Subject: Re: WANTED Inexpensive ethernet thinwire repeater. Message-ID: <667@cfa.cfa.harvard.EDU> Date: Wed, 9-Sep-87 17:56:55 EDT Article-I.D.: cfa.667 Posted: Wed Sep 9 17:56:55 1987 Date-Received: Fri, 11-Sep-87 05:37:23 EDT References: <1467@aramis.rutgers.edu> Organization: Harvard-Smithsonian Ctr. for Astrophysics Lines: 76 in article <1467@aramis.rutgers.edu>, hobson@aramis.rutgers.edu (Kevin Hobson) says: > >> >> I have a local area VAXCluster consisting of a '750 and a >> uVAXII. I am intending to ad a VAXstation 2000 to this LAVC. >> The '750 and uVAXII are both on a DELNI which is hooked to our >> standard baseband (thickwire) ethernet. >> >> The VAXstation has a thinwire ethernet port. DEC wants to >> sell me a baseband to thinwire repeater (DEMPR) for $4320 (Cdn) >> just to hook this little rascal up. > ... >> Who manufactures an inexpensive baseband to thinwire >> repeater? Even names and addresses (phone numbers) of ethernet >> hardware manufacturers would give me someplace to start. > > > Cabletron Systems Inc. > P.O. Box 6257 > East Rochester, N.H. 033867-6257 > (603)332-9400 > > MT-500-01 Transceiver with user selectable "heartbeat" (In other > words, can be use as Ethernet Version 1, 2, or IEEE > 802.3 transceiver) > > MT-500-03 Same as above with intrusive BNC-Series tap for use with > Thin Ethernet Coaxial Cable (In other words, this > device with MT-500-01 or local repeator (LR-2000) and > transeiver cable should help you) These are `ST500-xx', not `MT'. The ST500-03 is the DESTA equivalent. And, there's no `or' about it. You need the local repeater, an ST500-01 or -02, and ST500-03 to do the above (see diagram below). You'd have power and plug/receptacle mismatches otherwise. > > LR-2000 Local Repeator (DEC DELNI-equivalent) No, this is the DEREP equivalent, at about 1.5k from Cabletron (I can't remember the exact price, because we get a discount, and I don't remember the list prices. The DELNI equivalent is the MT-800. > > MR-9000C Multiport Repeator (DEC DEMPR-equilvalent) > [...] We have one of these and are happy with it. So, assuming the Ethernet topology restrictions aren't violated by the new repeater: <===X===========================X=============> (trunk Ethernet cable) | | | (xceiver cable) | | | --------- ------------- | DELNI | | repeater | --------- ------------- | | | | | | 750 uVax x---------X---------------T--------x (thinwire) (ST500-03) ---------- | VS2000 | ---------- What we'd all like (and is rather hard, so I understand) is a `reverse'-DESTA. No one makes them, as far as I know. -- Bill UUCP: {seismo|ihnp4}!harvard!cfa!wyatt Wyatt ARPA: wyatt@cfa.harvard.edu (or) wyatt%cfa@harvard.harvard.edu BITNET: wyatt@cfa2 SPAN: 17410::wyatt (this will change, sometime)