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From: imp@jhereg.osa.com (Charles T. Lukaszewski)
Newsgroups: comp.dcom.lans
Subject: Re: Implementing LAN using RS-232 Serial Ports
Message-ID: <1990Oct25.002828.7382@jhereg.osa.com>
Date: 25 Oct 90 00:28:28 GMT
References: <1990Oct15.030111.28548@eagle.lerc.nasa.gov>
Organization: Open Systems Architects, Inc.
Lines: 30

In article <1990Oct15.030111.28548@eagle.lerc.nasa.gov> tidedu@
mars.lerc.nasa.gov writes:
>I have heard that it is possible to utilize RS-232 serial ports
>on each computer to implement the network. If anyone has heard
>of (Or done) this, I'd be interested in knowing the BEST, and 
>MOST EFFICIENT way this can be done. I would particularly be 

If this is really the method you wish to use, there are a number of imple-
mentations of this style of network, which fall into two categories.  The
first category would be standalone systems like the system from Newbridge
Networks which use concentrators and home runs in a star-like topology.
(There are many others - I'm not endorsing Newbridge per se).  The second
method is to use a private branch exchange (PBX) that is capable of 
switching between RS-232 devices.  I know that Rolm has such a beast, and
that Northern Telecom used to have something like this.  Again, others
can probably provide more specifics, but these are the basic routes.

In my opinion, RS-232 based networks are more cumbersome than helpful.
By definition, your throughput will be at least several tens (Arcnet) to
several hundreds (Ethernet) of times slower.  Also, it is arguable whether
the one-user-at-a-time limit isn't any worse than Ethernet.  You might
at least cost-compare building an Ethernet or Token-Ring network with a
non-server based Network Operating System like Tops.


-- 
_______________________________________________________________________________
Charles T. Lukaszewski            imp@osa.com                      612 525-0000
Managing Partner & Chairman                       Open Systems Architects, Inc.
 "Who needs a disclaimer? I liked the opinions so much, I bought the company!"