looking to setup a wifi network

[Joseph Mack NA3T]

The situation:

	I would like to setup a connection to the internet for a random
group of people (a group of about 500 amateur astronomers who stand out in
a large cold field all night for a week looking at the stars and who sleep
most of the day), who get together once a year.

	I'm thinking of a laptop acting as a dhcpd/NAT box/squid connected
to the internet by ppp 56k modem (I would set this up on one of my random
linux boxes). Because the people are dispersed, running cables and hubs
will be expensive, and it seems simplest to expect people to have wifi
cards. I expect the first time to have a max of 50 people who want to try
this. (many people have computers to control their scopes, some will want
to keep up with e-mail and want to look at weather forecasts - to see
cloud cover etc). Since we're out in the styx, organisers will want to
exchange e-mail with people coming from afar.

What I want to know:

since the setup will be only used once a year, I would like the hardware
to at least be useable (not obsolete) for 5yrs. (I also would like this to
be as cheap as possible). I understand new wireless cards are coming out
at 2.4GHz. A they going to obsolete current cards in a year or 2?

Is the wireless card at the NAT router/squid I'm setting up any different
to the wireless cards that the people in the field will be using? ie do
wifi cards peer with each other (like ethernet cards do), or is it more
like ethernet cables, where the cable attached at one end to a NIC has to
connect at the other end to a hub/switch?

I understand that recently (whatever that means) that wifi cards are using
an agreed protocol and that cards from different manufacturers can now
talk to each other. If I used one of these cards, what percentage of
random people might I expect to be using the older cards and not be able
to connect to my setup?

I expect that if these is technically feasible and cheap enough, that I'd
announce ahead of time that the event would have internet connectivity
that people would need to bring a wifi card with such and such specs.

Thanks Joe

-- 
Joseph Mack NA3T EME(B,D), FM05lw North Carolina
mailto:jmack@wm7d.net azimuthal equidistant map
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