Path: utzoo!yunexus!ists!eric
From: eric@ists.ists.ca (Eric M. Carroll)
Newsgroups: comp.dcom.lans
Subject: Re: line-of-sight technology
Message-ID: <2535@ists.ists.ca>
Date: 11 Nov 89 00:59:01 GMT
Article-I.D.: ists.2535
References: <1989Nov9.175018.26644@hellgate.utah.edu>
Reply-To: eric@ists.ists.ca (Eric M. Carroll)
Organization: Institute for Space and Terrestrial Science
Lines: 19

>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?

ISTS has installed a LCI Lace laser from one building to another, about
0.85 km away. After lots of trouble with low serial number design problems,
we have got it settled in and it performs very well. We are quite happy
with it. Compared with the microwave (way out of budget) or T1
(ludicrously expensive in Canada), it was the clear choice.

As to the fog issue, it is the one weather condition that actually
brings the link down. Rain has not been much of an issue. Intense fog 
has brought it down once in 4 months. Generally the fog has to be 
enough that you have very limited visibility, but the situation has
not occurred enough to make any definite statements about fog survivabilty.