[1390] in linux-net channel archive
Re: Packet radio
daemon@ATHENA.MIT.EDU (John Paul Morrison)
Thu Nov 16 14:41:29 1995
From: John Paul Morrison <jmorriso@ConcordPacific.com>
To: drew@poohsticks.org (Drew Eckhardt)
Date: Wed, 15 Nov 1995 15:24:10 -0800 (PST)
Cc: linux-net@vger.rutgers.edu, linux-hams@vger.rutgers.edu
In-Reply-To: <199511152209.PAA19309@chopper.poohsticks.org> from "Drew Eckhardt" at Nov 15, 95 03:09:35 pm
>
> In message <199511152134.NAA21788@orange.ConcordPacific.Com>, jmorriso@ConcordP
> acific.com writes:
> >Do you mean *amateur* packet radio? Or commercial spread spectrum
> >radio - I don't think it's normally called packet radio (like WaveLAN
> >or Cylink). There are some commercial packet radio networks, but they
> >are slow (email systems similar to pagers)
>
> My original thought had been amature, although in reality I'm open
> to anything faster than 56K which will work in a point-to-point setup,
> almost line of sight, over 10ish miles.
An amateur system can be a rewarding experience, if you're up to it.
For 56kbps the traditional way to get online has been to roll your
own, or build a kit. It's also pretty expensive since the market is so
much smaller. Costs are at least CDN$1000 an end once you add in
interface cards, modems, power amplifiers and frequency transverters,
antennas. Then you have to build and test and hope it works :-)
Most of the 56kbps amateur activity has been broadcast rather than
point-to-point, that way a whole community can be served. But
point-to-point is possible too; you can even do full-duplex, compared
to broadcast which is basically CSMA. Spread spectrum systems are
limited to very low power, so poin-to-point is the only way that works.
Amateurs can put up 50 Watt repeaters and give good 56kbps coverage in
the hundreds of square kms.
we should continue this on linux-hams@vger.rutgers.edu for the amateur
radio stuff. In a nutshell, all the protocols and hardware
(synchronous serial cards) needed for 56kbps are supported in Linux.
for more 56kbps amateur radio info see http://hydra.carleton.ca and
http://www.mindspring.com/~bobm/ There's some pre-fab equipment coming
available for 56kbps too.
>
> >The spread spectrum stuff would be faster and cheaper, not to mention
> >easier to setup. With the right antennas and a clear path you can go
> >at least 13 km (I know a guy who does) or more.
>
> Can anyone nail down a price for this sort of setup?
I think WaveLAN (2 Mbps) cards cost under $1000 an end (Canadian
dollars and taxes etc. they're probably no more than US$400 but I
don't know). You can spend much more if you want higher speed, or
higher spreading gain (less susceptible to jamming or interference).
Hardware DES or IDEA encryption costs more too. I've seen units that
are up to $10,000 an end. There's even T1/E1 devices, presumably you
could haul telephone trunks :-)
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John Paul Morrison Concord Pacific Developments VE7JPM
jmorriso@ConcordPacific.com +1-604-895-8270 FAX: +1-604-683-2668
1000, 1095 W. Pender Street, Vancouver, BC, Canada, V6E 2M6
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