Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!iuvax!purdue!bu-cs!kwe
From: kwe@bu-cs.BU.EDU (kwe@bu-it.bu.edu (Kent W. England))
Newsgroups: comp.dcom.lans
Subject: Re: line-of-sight technology
Summary: consider Ethernet-over-microwave
Message-ID: <42476@bu-cs.BU.EDU>
Date: 13 Nov 89 17:35:48 GMT
References: <1989Nov9.175018.26644@hellgate.utah.edu>
Reply-To: kwe@bu-it.bu.edu (Kent England)
Followup-To: comp.dcom.lans
Organization: Boston U. Information Technology
Lines: 45

In article <1989Nov9.175018.26644@hellgate.utah.edu>
 haas@cs.utah.edu (Walt Haas) writes:
>
>We are considering options for a high-speed data link between our campus
>network and the computers in LDS Hospital, about three miles away.  There
>is a good clear line-of-sight between here and there, which would suggest
>that some sort of microwave or laser link would be useful.  However for
>a number of weeks each winter the air in between is filled with thick
>freezing fog.  Is anyone out there familiar off-hand with a good technology
>for dealing with this stuff?
>
	You can consider private laser or microwave.  I think that
laser will be ruled out as all the vendors quote one kilometer
maximum.  Fog is a killer for infrared laser.  Less so for microwave.

	23 GHz microwave should work well on a three mile link with
two foot dishes, depending on your definition of "thick".  Three miles
is well within nominal delay spec for Ethernet on microwave, so that
should work without special kludges.  Ethernet is cheaper than T1 last
I looked, and you get more bandwidth.

	If you want to talk to a vendor, call:

	Microwave Bypass, Inc.
	25 Braintree Hill Office Park
	Braintree, MA  02184
	(617) 843-8260
	dtheombs@eagle.mit.edu

	If I knew another turnkey Ethernet-on-microwave vendor, I
would tell you.  Motorola resells MBS gear, and perhaps Microwave
Networks in Houston is still in the business.  DEC and M/A Com never
did work.  LAN Connection never got off the ground.  I never heard of
anyone else.

	This technology has been used to good effect in NEARnet in the
metro Boston area, where there are 8 of these links installed to date.
I am getting another one to get to our Medical Center on the other
side of Boston.  Mass General also uses two links.  All from MBS.

	--Kent England, Boston University

	[Disclaimer:  I have no affiliation with MBS and this is not
intended as a sales pitch.  Your mileage may vary.  Second opinions
always advised.]