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Date: Thu, 20 Mar 1997 13:40:04 -0800 (PST)
From: Doug White <dwhite@gdi.uoregon.edu>
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Reply-To: Doug White <dwhite@resnet.uoregon.edu>
To: Luigi Rizzo <luigi@labinfo.iet.unipi.it>
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Subject: Re: a networking question...
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On Thu, 20 Mar 1997, Luigi Rizzo wrote:

> sorry if I abuse of this group for a partially unrelated question...
> 
> I am having a hard time in finding cheap Ethernet repeaters with
> BNC ports, whereas 10 Mb/s HUBs with 10BaseT RJ45 ports are now
> available for about $15/port.  Is it possible to connect the AUI
> port of a BNC transceiver to the Tx/Rx pairs of an RJ45 port and
> make the connection work ? (of course with an external power supply)

No.  The transmission medium is entriely different.  Coaxial cable
requires different power levels and encoding.  There's only one wire in
there, and you need 4 for utp.

The problem here is that BNC is designed as a "bus" topology, not a "star"
medium like UTP.  BNC hubs sort of 'short-circuit' this layout.  I suspect
it requires intricate circuitry to manage the ports, plus this sort of 
topolgy is very, very rare.  Heck, Coax is pretty rare nowadays because
it's such a pain to manage and is easy for one workstation to break the
whole network (literally).

Doug White                              | University of Oregon  
Internet:  dwhite@resnet.uoregon.edu    | Residence Networking Assistant
http://gladstone.uoregon.edu/~dwhite    | Computer Science Major