While it's long been possible to connect computers via radio waves, it didn't really become practical for most of us until the tech industry agreed on a standard.
That standard, certified by the Institute of Electrical and Electronics Engineers as IEEE 802.11b, refers to a technology that uses the 2.4 gigahertz (GHz) radio spectrum to transmit wireless signals that can be used to connect computers to an organization's local area network or, through the network, to the Internet for Web surfing, e-mail, chatting or any other Internet service.
The technology is not only being used in offices and homes but in a growing number of public "hot spots" such as airports, coffee shops, hotels and cafes where people can access the Internet on their own laptops without having to plug in any wires. There are even some free public access areas such as Bryant Park in New York. To search for hot spots, visit www.pcanswer.com/hotspots.htm.
The 802.11b protocol also is being used to connect consumer devices. TiVo, which makes personal video recorders that use hard drives instead of tape to record TV programs, is starting to allow customers to use 802.11b networks to connect their TVs to their home PCs so that the TV can be used to view digital photos or listen to digital music stored on the PC.
In addition to the IEEE certification, about 200 industry players have formed the "WiFi Alliance" (WiFi is short for "wireless fidelity") that certifies "interoperability" of 802 products. The alliance is trying to train consumers to look for its WiFi logo on products as an assurance they will be compatible with other WiFi products.
Yet despite the standards and the trade alliance, there is still some confusion in the marketplace due to the continual evolution of the technology. The 802.11b standard transmitting data at up to 11 megabits per second is pretty much set in stone, but newer and higher speed standards are being used in products that are just starting to hit the market.
Before I get into how these standards do and don't interact, let's review the pieces of a wireless network.
Any computer that communicates with an 802.11 network needs to have a wireless network adapter either built into the machine or added via a plug-in card. Most notebook makers now include optional built-in adapters on their latest models, but any notebook PC can be equipped with a wireless card that slips into its PC card slot. There are also wireless adapters that connect to a USB port of a desktop or laptop computer.
The network itself needs to have a wireless base station called an "access point." In some cases, these are small and inexpensive (under $100) radios that work in tandem with other network equipment, or you can buy a somewhat more sophisticated wireless router or gateway that connects directly to your DSL or cable modem or, in some cases, replaces your DSL or cable modem. For example, 2Wire makes a line of DSL wireless gateways that plug directly into your DSL phone jack as the only equipment you'll need other than the wireless network adapter in your laptop or desktop PC.
WiFi equipment doesn't directly provide an Internet connection. It's your link to the network but you still need a DSL, cable modem or some other Internet connection.
In addition to 802.11b there are two newer technologies. Operating at 54 mbps - roughly five times the speed of 802.11b - 802.11g is built into some of Apple's newest Macintosh laptops. Like the "b" standard, it uses the 2.4 GHz spectrum and is backwards-compatible with b. That means that someone with a new Mac or any other computer with an 802.11g wireless radio can still communicate with the older 802.11b access points.
The other technology, 802.11a, operates at 54 mbps, but it uses a different radio spectrum (5 GHz), and the bad news is that it's not compatible with 802.11b or 802.11g.
But there is good news. Companies that make 802.11a access points and cards typically offer "dual band A+G" equipment, which means they are compatible with the g standards and, therefore also backwards-compatible with b. So, if you buy a system that supports both a and g, you're able to communicate with any WiFi certified wireless equipment on the planet.
So, with all these numbers and letters, what should you do?
The reality is that the older standard 802.11b is fast enough for virtually any of today's Internet connections. That's because that standard, while almost a fifth the speed of the newer 802 systems, is still at least five times faster than any Internet connection you're likely to encounter. The Internet connection, not the wireless connection, is really the bottleneck for e-mail and surfing the Web.
There are people who could benefit from the faster 54 mbps connections but only if they are doing computer-to-computer connections and, then, only if they have some need for high-speed communications such as playing interactive games or streaming video over the network. Those applications do exist, but they're still not all that common.
Bottom line: If you're buying a system to use today, definitely get one that is compatible with 802.11b. That means either get 802.11b, get an 802.11g card that's backwards-compatible or - for the best of all worlds - get a dual-mode card that supports 802.11a and 802.11g.
A syndicated technology columnist for nearly two decades, Larry Magid serves as on air Technology Analyst for CBS Radio News. His technology reports can be heard several times a week on the CBS Radio Network. Magid is the author of several books including "The Little PC Book."
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By Larry Magid