Path: utzoo!utgpu!watserv1!watmath!att!att!emory!wuarchive!psuvax1!rutgers!aramis.rutgers.edu!athos.rutgers.edu!hedrick From: hedrick@athos.rutgers.edu (Charles Hedrick) Newsgroups: comp.dcom.lans Subject: Re: Ethernet vs. ARCnet for a Novell lan Message-ID: Date: 30 Oct 90 04:23:05 GMT References: <1990Oct29.161448.24234@cs.odu.edu> Organization: Rutgers Univ., New Brunswick, N.J. Lines: 33 Ethernet and arcnet are similar technologies, except that Ethernet is faster. It's less expensive because there are much more Ethernet users, so production volumes are higher. If a station goes down on Ethernet, there is no effect. It is in principle possible to shut down any network due to one station doing something wrong, if the things is sufficiently pathological, but the Ethernet design attempted to protect against as many as possible. Actual results are that they were pretty successful. If a station just has its software hang, that's not even a dangerous situation for the network. Of course if the software gets into a loop sending packets continuously, it's pretty hard to expect any network technology to do much to fix that. It won't necessarily take down the network, but it will certainly create a heavy load. Thinnet (thin coax) is generally cheapest for a lab situation, i.e. lots of machines in one room. The disadvantage is that it sort of like old Christmas tree lights (or Localtalk), in that one person disconnecting their cable will disrupt the network. If it's in one room this shouldn't be a problem, but with lots of user offices it could be. The reason thinnet is cheap is that it needs no electronics beyond what's on the controller card. Beyond that, the usual recommendation these days is unshielded twisted pair. It's easy to expand, and easy to do network diagnosis on. It also has a single point of failure, the box in the wiring closet that all the wires go to. This seems not to bother people. I sort of like the original thick coax myself. But I have to admit if somebody blows installation of a tap, it can short the cable and you may have a hard time finding it. The nice thing about the twisted pair stuff is that the wiring to one office can't affect other offices. In this respect it's better than the other Ethernet technologies (or Token Ring). Basically though any of the wiring schemes have their advantages and disadvantges, and probalby about all work out the same, as long as you are careful.