Xref: utzoo comp.dcom.lans:3017 comp.protocols.tcp-ip.ibmpc:1406 Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!elbereth.rutgers.edu!ron.rutgers.edu!ron From: ron@ron.rutgers.edu (Ron Natalie) Newsgroups: comp.dcom.lans,comp.protocols.tcp-ip.ibmpc Subject: Re: Wide Area Network Keywords: token ring, twisted pair Message-ID: Date: 20 Jun 89 00:54:55 GMT References: <1300@lafcol.UUCP> Organization: Rutgers Univ., New Brunswick, N.J. Lines: 33 o Using Token Ring over Twisted Pair (IBM, Proteon, U-B, etc) Most of the popular token ring implementations use twisted pair. Both IBM and Proteon. o Bridging Token Rings to 802.3 LAN Bridging has a very funny meaning with regard to source routing packets and route discovery in the IBM Token Ring environment. However, some products are already available to route IP packets between token rings and Ethernets. o Bridging VAXen to Fiber Optic Token Ring (IBM or Proteon) Proteon has made UNIBUS boards for their token ring. I'm not sure if an IBM Token Ring is available. Again if it's IP traffic you could use Ethernet on the VAX gatewayed to token ring. o Use of shielded vs. unshielded cable Proteon requires shielded cable (they signal the wirecenter using a DC voltage on the diferential pairs and use the shield as a reference. IBM specs unshielded twisted pair in some circumstances for the older 4 MB TR, but they are now pretty much recommending shielded everywhere. o Use of fiber to the faceplate (single mode or multi mode) Fiber is still pretty costly, mostly because the units at the end are expensive, but that's likely to come down in time. You probaby want multimode. Single mode is much too costly for the purpose of running to individual workstations. -Ron