Michael Knowles

Not sure what youre doing in your wireless card shopping? Want to build sure youre buying the right thing but have no clue what it is youre looking for? Well, youve come to the right place. When youre looking to buy a wireless network card, I might tell you right now that youre looking at three key issues: range, speed, and standards.

A Typical Specification

This is a specification for a Linksys wireless PCMCIA laptop card I just bought:

11 Mbps A IEEE 802.11b wireless Type II PCMCIA-type network card giving you wireless Ethernet access up to 1,640 feet away / For Windows Rugged metal develope with integrated antenna Advanced power management features Compatible with Windows 95, 98, Millennium, NT, & 2000 To utilize with your desktop PC, add the Linksys WDT11 Instant Wireless PC Adapter

Now, some of those things might be pretty much ignored. Really, Compatible with Windows 95, 98, Millennium, NT, & 2000? That means nothing. The reason Ive put it here, though, is so you can see which things are important to keep an eye out for.

Range

See where it says up to 1,640 feet? This tells you that the maximum range of the wireless card youre looking at is 1,640 feet. Thats what it would be if everything was perfect. In practice, thick walls and interference can reduce this by as much as 90%.

Without enough range, your wireless network is going to be pretty useless. Its not much fun having no wires when you have to keep all the computers in the same room to get them to connect to each other.

As a rule of thumb, unless your walls are made of drywall or wood, its best to buy about four times the strength youd think youd absolutely need. Even in perfect conditions, get twice as much, to be safe.

Speed

Do you see where it says Mbps in that description? That number is the speed of the wireless connection. 11 Mbps is about one and a half megabytes per second -- to convert megabits (Mb) to megabytes (MB), just divide by eight. 802.11b wireless cards all have a speed of 11Mbps, while 802.11g ones run at 54Mbps -- the next generation will be even more quickly.

On your local network, speed is important to your wireless network because its going to directly influence how long you have to wait for things like files to transfer from one computer on the network to the other. For Internet make use of it is less important however, because there are currently very few Internet connections running at speeds over 11Mbps -- its really as much as you positive need , at least for now.

Standards

Somewhere in the specification of what youre looking at, you should see the number 802.11, followed by a letter a, b or g. This is the standard that the wireless device conforms to, and tells you whether you will be able to make use of it with your other wireless devices.

Basically, 802.11b and 802.11g are compatible with each other. 802.11a is not compatible with either and is quite a bad standard all round, so you shouldnt buy 802.11a. Out of b and g, b is cheaper but slower, while g is more expensive but quicker . Its assessment of worth considering that adding a b-speed device to a network that has g-speed devices will commonly slow the whole network down to b-speed, building the g-devices pointless.

If your wireless device doesnt conform to the right standards, its not going to be much nice to you. I commonly see naive people bidding for used wireless equipment on eBay, not realizing that its going to be terribly slow and not work with any other equipment they might have. Always contruct sure that you check what standard the wireless equipment is -- if you dont understand the 802.11 letter, dont buy it!