Wi-Fi Vs. Cellular Data: Making the Right Connection

For connecting to the internet while away from the home or office, users can increasingly choose between cellular data networks, such as GPRS (General Packet Radio Service) and 1xRTT, and 802.11b-based wireless hot spots. Each connection method has its pros and cons, but the best solution may be a mixture of the two.

T-Mobile is moving in this direction. It currently offers a price break on hot-spot access for its mobile subscribers, and it is working on enabling a service designed to facilitate handoff between GPRS and Wi-Fi networks (choosing the method that best fits the environment).

In the meantime, there are a number of things to consider when deciding which connection method will work best, including:

Speed: So-called 2.5G cellular data networks tend to deliver speeds between one and two times the speed of a 56K-bps dial-up connection—not bad for e-mail and light browsing, but well below what office workers and home broadband subscribers have come to expect and depend on. Although youll never see anything near the 11M-bps speeds breathlessly proclaimed by Wi-Fi marketers, we regularly experienced speeds of about 1,200K bps at the hot spots we tested.

Coverage: With a range of about 100 feet per access point, dont hold your breath for Wi-Fi-anywhere connectivity, no matter how steep the hot-spot growth curve becomes. Cellular data networks dont reach everywhere, either, but they do cover nearly every place from which you can place a wireless phone call today.

Hardware availability: If you buy a new notebook computer today, chances are it has an 802.11b radio built in. (Even handheld computers now commonly include Wi-Fi capabilities.) If not, prices for add-on wireless adapters have fallen precipitously, and these adapters are available in PCMCIA, Universal Serial Bus, CompactFlash, Secure Digital and MiniPCI form factors. GPRS or 1xRTT radios are significantly harder to come by and cost quite a bit more. In addition, wireless carriers havent helped their cause by sticking stubbornly to device- specific data connection cables and dragging their feet on adoption of Bluetooth in their phones.

Cost and billing: Provided you can find Wi-Fi hot spots in areas from which you frequently need connectivity, a $50 subscription to a Wi-Fi network can go a long way. (And many public access points are free of charge.) Of course, while hot-spot aggregators such as Boingo Wireless Inc. and Gric Communications Inc. are working to harmonize billing and log-in (see review, Page 51), the immaturity and inherently scattered nature of hot spots can make accounts tricky to manage. Cellular data access can be more convenient, but this convenience doesnt come cheap: Costs associated with metered data plans add up quickly. Whats more, time is money, and slower data rates can take a bite out of productivity while on the road.