Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!usc!zaphod.mps.ohio-state.edu!van-bc!rsoft!mindlink!a127
From: a127@mindlink.UUCP (Dave Norman)
Newsgroups: comp.sys.amiga.hardware
Subject: Re: Networking options
Message-ID: <1696@mindlink.UUCP>
Date: 7 May 90 05:50:18 GMT
Organization: MIND LINK! - British Columbia, Canada
Lines: 26

I missed the earlier conversation on this topic but since I do novell support
and distribute network card perhaps I can be of help.Novell supports
approximately 25 different network topologies but in Canada the most popular
are Arcnet and Ethernet.  Arcnet is a token passing network which has a
transmission speed of 2.5 Megabits per second and is available in either a star
(ie hub configuration) or linear bus wiring scheme.  Each has their fits but
also their limitations.  Arcnet can be wired with either RG62Au coax cable with
90 Ohm termination or with twisted pair cable if the NIC (network interface
card) is built to accept TP.  TP wiring can be added to a Coax nic by adding an
impedance matching tranformer to the coax BNC conector (called a BALUN).
Advantages of token passing networks are easy expansion less chance of complete
lan failure due to one bad connection, ability to remove a node without downing
the network, and a linear degrading of access speed with increased nodes.
     Ethernet (IEEE 802.3 ) is a CSMA / CD network which stands for Carrier
sense multiple access / Collision detect.  The transmission speed is 10 Mbits
per second.  Cable is either rg58 au (50 OHM) called thin ethernet or slang
"cheaper net" with bnc connectors brought to each linearly wired terminal
through a "T" connector with a 50 Ohm terminator on each end of the cable.
CSMA / CD nets have a non linear degradation with increased nodes as the
likelihood of a "collision" of two nodes trying to talk simultaneously increase
exponentially with number of nodes and network traffic.  So the greater
bandwidth of ethernet is hindered by its collision detect everybody try again
algorithims.  The best source of data on these and other topologies without
getting too technical is from a book "Installing Netware" I will try to get my
copy back so I can give you the ISBN press and author information.  logging out
for now   Dave Norman