Wireless LAN setup

You will need a Wireless Router which will provide the Laptops with DHCP to connect to the remote site network via a ethernet cable, depending on the network you may need a crossover cable or a stright through, carry both.  The laptops only require a wifi card, which all do now a days.  A single access point should be fine.  The laptops will be configured as a workgroup.

Kutyi,

Thank you for your input.  Some locations will not have a network or did I misunderstand you comment .  Can 25 computer connect to one router?

Yes 25 can connect just fine.  I use Linksys WAP54G with 30 laptops without issue.  Get a Linksys WRT54G for a router.  A router will work better as it will provide DHCP to you laptops, if you connect the WAN port to the remote network then you can ride their Internet out so long as the routers WAN interface is set to DHCP.  Make sure that your dhcp scope on the LAN side of your interface is setup so as to not be the same as the networks you would connect to or you will have issues.  If the site has no network then your laptops will not get the internet.  If you have a printer for this portable lab you can connect directly to a LAN port on the router to allow your laptops to print.

Kutyi,

You lost me,  I have no IT background and don't understand the lingo.  
I've read about routers, is Linksys WAP54G a different model router than the one you recommended, WRT54G?  What is a WAN port is that the WAP54G?

What am I connecting the WAP port to? I can't decode "if you connect the WAN port to the remote network then you can ride their Internet out "  Please define remote network. Whose internet internet can I ride out?  Why is this desireable?

If the site has no network you say I can't get to the internet.  Isn't that what the broadband cards do?

Jean

A WAP54G is not a router, but I believe the router is better for your circumstance.  A WAP(Wireless Access Point)  is a slightly different type of device, you want a router.  On the back of the router there are ports, where wires plug in, one is a WAN port to connect to the remote network, the others are for anything you want in you mobile lab.  The WRT54G offers these ports plus wireless capibilty.  You may want to hire a local computer firm to set this up for you.  If you want to use a Broadband card then contact your Broadband provider and see what is required to connect to them.

While Linksys makes a few routers that can do what you want (WRT54G3G-xx), I suggest you get a DLink. Have a look at these: http://www.dlink.com/products/category.asp?cid=108&sec=1

The latest and greatest is the Kyocera KR-2 (made by Cradlepoint), but those are quite expensive.

If you have a regular route compare it to the coverage maps of the carriers in your area.
e.g.
http://www.wireless.att.com/coverageviewer/
http://www.verizonwireless.com/b2c/CoverageLocatorController?requesttype=NEWREQUEST/
http://coverage.sprintpcs.com/IMPACT.jsp?covType=sprint

And any other carriers that offer EDGE/EVDO/UMTS/HSDPA wireless data plans in your area.
(Be sure you're looking at the data coverage maps, not their regular voice service maps.)

Then coordinate your purchases so you get an adapter that will plug into the router you choose. I don't think either of those DLink units take PCM Express cards (the triangular tip 34mm cards most newer laptops take, rather than the full width PCM/CIA cards... the KR-2 takes the Express cards, though, if that's what your laptops all take... it's nice to be able to plug the card into a laptop for troubleshooting if something's wrong and you don't know if it's the router or the card).

Oh, and if you can keep it down to a 1 year contract by paying say, $50 more for the card, I would do that... hopefully the providers won't be too slow rolling out WiMAX when broadcasters clear the analog TV frequencies in February 2009, and a 1 year contract started soon should be coming to an end just about the time they have that up and running, with any luck.

Here is basic steps: http://www.microsoft.com/athome/moredone/wirelesssetup.mspx

Start shopping for router, I recommend the Linksys:
http://www.linksys.com/servlet/Satellite?c=L_Product_C2&childpagename=US%2FLayout&cid=1175239525280&pagename=Linksys%2FCommon%2FVisitorWrapper&lid=2528052539B02

Also, check the laptops see if they have wireless built-in or you have to buy wireless cards:

http://www.linksys.com/servlet/Satellite?c=L_Product_C1&childpagename=US%2FLayout&cid=1117775462965&pagename=Linksys%2FCommon%2FVisitorWrapper&lid=6296539789L05

Sorry, aldridgedj - they seem to have missed the criterium of having internet access wherever you go, not dependent on someone else providing a connection. The EVDO/HSDPA cards will do that for you. If there's internet available, fine - hook cat5 from their internet to a port on the router and use it as an AP. But if there isn't internet available where you're at, plug a 3G card into the router and have it dial the nearest tower for access... pretty much anywhere there's cell phone access there can be data access too.  If you're going to look at any Linksys products, search for WRT54G3G on linksys.com - they make models for Sprint, Verizon and ATT service (indicated by the suffix after the WRT54G3G).

Wireless N may be the standard of the future, but it's simply not necessary for sharing a 1-12 Mbps connection among 20 notebooks.  Heck, it's probably not needed for sharing even a 45 Mbps T3 connection among 20 notebooks.

What type of service were you planning on purchasing?  Some are cell based and some are wifi wireless based.

Thank you for your help.  Using the information you sent, I did some research and now understand how to configure my setup.  Rest assured, I will hire professionals to actually do the work but wanted to understand the basics.

Deciding how to divide the point was difficult and took longer that it did to answer the question.  Katy1 you definitely got me started, thank you.  Darr247, you saved the day, explaining how to set up wirelessly was critical and for that I thank you.