Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!pasteur!ucbvax!decwrl!labrea!glacier!jbn
From: jbn@glacier.STANFORD.EDU (John B. Nagle)
Newsgroups: comp.sys.next
Subject: Re: practical details (Thin <-> thick Ethernet)
Message-ID: <18167@glacier.STANFORD.EDU>
Date: 14 Mar 89 16:55:23 GMT
References: <2878@stpstn.UUCP> <1718@ucsfcca.ucsf.edu>
Sender: John B. Nagle <jbn@glacier.stanford.edu>
Reply-To: jbn@glacier.UUCP (John B. Nagle)
Organization: Stanford University
Lines: 34


      All you need is a BNC to N cable adapter.  This was all covered
about two months ago in this newsgroup.

      Bear in mind the following:

      1.  When you do this, the entire cable becomes subject to thin
	  Ethernet length limitations.  (This is an overly conservative
	  assumption, but unless you're comfortable using a time-domain
	  reflectometer on your Ethernet, it's a good rule to follow.)

      2.  The BNC T connector always goes on the back of the computer.
	  Don't insert any cable between the computer and the T connector.
	  If you do, the network may behave very strangely; some machines
	  won't be able to talk to some other machines.

      3.  Of course, if anyone disconnects a cable from the T connector,
	  the whole net goes down.  You can disconnect the T from the
	  computer freely, but the cables must remain attached.

      4.  For small nets, a good rule to follow is to just hook the 
	  thin Ethernet on the end of the thick one, using a BNC to N
	  adapter of the appropriate gender to replace the terminator.
	  Then, terminate the new thin Ethernet at its end with a thin
	  Ethernet terminator, or with a thick Ethernet terminator
	  and another BNC to N adapter.

      5.  The BNC to N adapter should be female-female, but these are hard
	  to find.  If you have to get a female-male, you can add on a 
	  standard "barrel" (a female-female BNC to BNC, or female-female
	  N connector) of the appropriate family.  These are available from
	  Arrow, Newark, Hamilton/Avnet, etc.

					John Nagle