| Most Windows-compatible laptops come with slots for expansion cards. (I'll show you in detail how these slots, sometimes called expansion slots, work later in this chapter in the section "Installing the Card.") These expansion slots are used to add hardware features to a laptop that it doesn't already have built in. For historical reasons, the cards that fit in the expansion slots are called PCMCIA cards. PCMCIA is short for Personal Computer Memory Card International Association, which is the name of the organization that has devised the standard for cards that can be added to laptops. (You can find out more about PCMCIA at www.pcmcia.org.) These days PCMCIA cards are commonly called PC Cards. They were originally designed to add additional memory to laptops, but have branched out to include devices ranging from dial-up modems to mini-hard drives, and more. You can see the same technology process at work today with PDAs that have a slot for CompactFlash memory cards. Wi-Fi devices can now be added to PDAs using the receptacle originally intended for the CompactFlash memory cards. In much the same way, PC Cards have come to be used for many other things besides memory, not the least of which is to connect to Wi-Fi wireless networks. In fact, it is pretty much the case with laptops that the original function of these cards, as memory expansion devices, has been forgotten. If your laptop is not equipped with Wi-Fi, and you want Wi-Fi (and who doesn't want Wi-Fi on their laptop?), you gotta go out and buy a Wi-Fi PC Card. Well, actually there is another possibility. You can use the USB or Ethernet ports on your laptop to connect a Wi-Fi receiver. For more information about this, see the "Other Options" section later in this chapter. In any case, for now let's assume you are going to add a PC Card to your machine (it is certainly the least expensive way to add Wi-Fi).  | Apple AirPort Extreme Wi-Fi cards work only with PowerBooks; they do not work with Windows laptops. Wi-Fi PC Cards used by Windows laptops do not work with Apple PowerBooks. |
A good starting place is understanding the differences between different Wi-Fi cards, and getting a handle on where you should buy one. Wi-Fi and the PowerBook If your mobile computer is an Apple PowerBook that is "AirPort ready" but not "AirPort enabled," your PowerBook didn't come from the factory with Wi-Fi capabilities. However, you can add a special card, manufactured by Apple, to your PowerBook. This card, called AirPort Extreme by Apple, uses a proprietary, easy-to-use, plug connection to attach to the PowerBook. tip  | If you are setting up a home network, you don't need an Apple AirPort Extreme Base Station to communicate with a PowerBook equipped with an AirPort Extreme card. The PowerBook will be capable of communicating with any 802.11b or 802.11g Wi-Fi base station or access point, regardless of brand. |
The Apple AirPort Extreme cards communicate using 802.11g Wi-Fi, which means that they also can "talk" to just plain vanilla 802.11b Wi-Fi. Although adding a Wi-Fi card to an Apple PowerBook is a fairly straightforward process, the same cannot be said for adding one to a Windows PC. Depending on your Windows computer, it can be a fairly grueling process. However, it is generally reasonably easy to slip a Wi-Fi PC Card into the appropriate slot in a Windows laptop. Differences Between Cards As you'll see when you start shopping for a Windows-compatible Wi-Fi PC Card, there is a plethora of cards to choose from. COMPARISON SHOPPING ONLINE If you use an online shopping comparison service such as CNET's, www.cnet.com, or Froogle, www.froogle.com, you'll need to search using a more generalized term than "Wi-Fi PCMCIA" to find most of the products available. You'll get the most products listed at CNET if you use the search term "wireless NIC." ("Wireless" is, of course, more general than "Wi-Fi"; NIC is short for Network Interface Card, which refers to add-on cards used both in laptops and desktop computers.) A search using the term on CNET yields over 140 products (not all of them will work with laptops, of course). The search term "Wi-Fi Card" works best at Froogle, yielding more than 250 distinct products. However, many of these products are not "cards" at all; this search yields access points and related Wi-Fi hardware as well as the cards you are looking for. If you just walk into your handy-dandy computer or electronics store and demand a "Wi-Fi Card," you'll do just fine. So my point is that if you want to spend some time comparison shopping online either to research or purchase it's a great thing to do, but takes a bit more finesse. |
So, how do you sort through all these choices? The good news is that it may not matter all that much what you choose: Wi-Fi certification means interoperability. (It also means never having to say you're sorry!) Starting from the premise that your choice of Wi-Fi card for your notebook is not an earthshaking issue because any Wi-Fi card will work, here are the criteria you might want to consider that differentiate one Wi-Fi card from another (these are ranked roughly in order of importance, with brand being last as an essentially irrelevant consideration): I'll discuss each of these criteria briefly so that you can be a more informed shopper when you set out to buy your Wi-Fi card. But remember: Almost any Wi-Fi card designed for a laptop will do. So don't sweat it too much! Supported Protocols The least expensive cards are 802.11b Wi-Fi cards. Because the predominant flavor of Wi-Fi networks is currently 802.11b, it makes some sense just to go for the inexpensive option. (For more on the differences between the 802.11a, 802.11b, and 802.11g Wi-Fi protocols, see Chapter 2, "Understanding Wi-Fi," and Appendix A, "Wireless Standards.") However, with a tip of the hat toward tomorrow, you probably should consider buying a 802.11g Wi-Fi card (these cards will also run on today's 802.11b networks). Although there is a cost difference, it is marginal and probably worth the hit to your pocketbook. Unlike 802.11g Wi-Fi, 802.11a Wi-Fi is not backward-compatible with 802.11b. So it probably does not make sense to buy a card that just works with 802.11a. Instead, if you think you want 802.11a (probably because you intend to use your laptop with a specific network that runs on 802.11a), you should get one of a number of Wi-Fi cards that support both 802.11a and 802.11b. These cards are sometimes referred to as dual band wireless cards. | Note that 802.11b Wi-Fi cards will operate on 802.11g Wi-Fi networks, just not at the faster 802.11g speeds. |
If you want to cover all bases (not a bad idea!), why not get a card that is compatible with 802.11a, 802.11b, and 802.11g? Price The price of computer hardware is always coming down. This implies that if you wait long enough they'll pay you to own a Wi-Fi card! If that's your plan, expect to wait a while. Currently, you can get a generic off-brand 802.11b PC Card for as little as $25 or $30 U.S. At the other end of the scale, if you knock yourself out, you can probably find a 802.11g card that costs more than $100 (which makes it comparable to the Apple AirPort Extreme). Range and Antennas The primary job of a Wi-Fi card is to communicate. A Wi-Fi card's ability to communicate in a seamless fashion is limited by its range. This means that range is one specification that it might make sense to check when you are buying a card. tip | It's only really worth worrying about range if you expect to be using your laptop more than a hundred feet or so from a Wi-Fi access point. |
A typical Wi-Fi card has a range of 200 300 feet, but some are rated for communication as far as 3,500 feet. (The actual distance you should expect to obtain depends on many factors including terrain, obstacles such as interior walls, and interference from other devices.) Most Wi-Fi cards use an internal antenna. You should know that some cards can be fitted with an external antenna that greatly extends their range. If an external antenna can be fitted to a card, it will be mentioned in the product specifications. You can also see if there is a small jack at the end of the card for the antenna. In some cards, such as the popular models made by Agere (and remarketed by Dell), this jack is covered with a small black plastic plug. Optional antennas are explained in Chapter 17, "Adding Wi-Fi Antennas to Your Network." Brands I am not a great believer in brand loyalty. However, considering the overall inexpensive nature of Wi-Fi cards, it makes sense to buy a "name brand" card so that you have some reasonable expectation of support in case you run into difficulty. Quality manufacturers of Wi-Fi cards include If you have feedback about this list a good experience with a product from a vendor not on this list, or a bad experience with a vendor on this list please feel free to contact me at wifireader@bearhome.com. Where to Buy You can easily buy a Wi-Fi card online at stores such as Amazon.com, Dell.com, or Buy.com. You can also use an online comparison shopping service such as Froogle, www.froogle.com, CNET, www.cnet.com, or PracticallyNetworked, www.practicallynetworked.com. (See the sidebar "Comparison Shopping Online" for more information.) Almost any consumer electronics, computer, or office supply store should also be able to sell you a Wi-Fi card. However, with the exception of a specialty store like Fry's, you are unlikely to find as much selection in the "real world" as you will online. | 