Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!bloom-beacon!spdcc!eli
From: eli@spdcc.COM (Steve Elias)
Newsgroups: comp.dcom.lans
Subject: broadband token bus (was: CATV networking)
Message-ID: <2530@spdcc.SPDCC.COM>
Date: 4 Feb 89 18:52:00 GMT
References: <1422@ucsd.EDU> <27676@bu-cs.BU.EDU>
Reply-To: eli@ursa-major.spdcc.COM (Steve Elias)
Distribution: all
Lines: 46

In article <27676@bu-cs.BU.EDU> kwe@buit13.bu.edu (Kent England) writes:
>
>	You might want to be careful about committing to the broadband
>token bus standard [802.4].  It may not go anywhere in terms of
>installed base.

	if broadband .4 provides the price & performance you need (extending
	ethernet subnets over many miles at nearly full speed), the
	installed base of other .4 products won't make much difference!
	
>	Ungermann-Bass has dropped support for the broadband token bus
>medium.  They say it is due to lack of market interest.  They will be
>supporting MAP on Ethernet and, I suppose, other IEEE media standards.

	good luck to them.  .4 to .3 bridges can enable .4 traffic 
	to traverse ethernets and interoperate with .3 nodes, as well.

>	U-B pioneered MAP support through INI, a joint venture with GE
>that GE bailed out of a while back.  U-B knows the MAP market through
>INI, so I would take their "advice" seriously and I question whether
>broadband token bus will ever reach a critical mass of support.  

	their "advice" might be due to internal factors which are
	not public knowledge! 

>	Anyway, broadband MAP is looking rather deadend-like.  But
>perhaps broadband token bus has uses outside of MAP.  

	it surely does have uses outside of MAP...

>interested to know what other users think and what other vendors
>already support 802.4.  Doesn't someone make a .3-.4 bridge already? 

	there are a bunch of .3 to .4 bridges available.  the company
	i work for (Chipcom) happens to make one of them!  .4 provides
	a great medium for extending ethernets to very long distances
	without paying leased-line costs, and without sacrificing
	performance (depending on whose bridge one uses)...  i'm sure
	you can all guess which bridge i would recommend..  the Chipcom
	bridge has performance far greater than any other .3-.4 bridge,
	though we are not yet shipping one with inband network management.



-- 
   Steve Elias (eli@spdcc.com) ((617 239 9406)) (((617 890 6844))) ()