If you need Internet access on the go, try cellular service. All major cellular providers offer Internet cards for your laptop. They slide into a PC Card slot, much like a Wi-Fi card.

The cards give you Internet access anywhere you have cellular coverage. The concept is simple, but deciphering the pricing and technical details can be confusing.

These days, cellular providers tout broadbandlike speeds. Certainly, the cards are far faster than dial-up. They fall short, however, when compared with cable and DSL speeds.

Some networks are faster than others. So it helps to understand the differences.

First, there is Enhanced Data rates for GSM Evolution. EDGE is a high-speed Internet service that is considered to be 2.5G, that is, between second- (2G) and third-generation (3G) cellular broadband services. It is provided by wireless phone companies that use Global System for Mobile Communications technology. Users typically experience speeds of around 200 kilobits per second for both downloads and uploads, although its theoretical limits are higher.

Evolution-Data Optimized is more advanced. EV-DO is a 3G high-speed Internet service provided by wireless phone companies that use Code Division Multiple Access technology. The average download speed is between 400Kbps and 700Kbps. Upload speeds average 300Kbps to 400Kbps. Still, it doesn't compare to cable broadband's average download speed of 7 megabits per second.

You may also encounter High-Speed Downlink Packet Access. HSDPA is a 3G high-speed Internet service. It isn't widespread yet, but its download speed can get up to 3.6Mbps or higher, which truly compares to broadband. HSDPA's uploads average 384Kbps.

Laptop cards generally cost about $200. But you can get steep discounts when you sign up for one or two years.

Sprint offers EV-DO laptop cards. For $60 per month, you'll get unlimited access to the Internet from your laptop. If you live in or travel to an area without full digital coverage, the card may revert to a slower network.

Verizon also uses EV-DO with its BroadbandAccess service. Unlimited data usage runs $80 per month. When the service isn't available, the card uses Verizon's NationalAccess service.

T-Mobile's laptop cards use EDGE. For $50 per month, you'll get unlimited data access. You'll also get unlimited access at thousands of T-Mobile HotSpots.

Cingular cards can use an EDGE network. They can also access Cingular's HSDPA network, where it is available.

Cingular's plans are more complicated than those other providers offer. You can purchase plans that offer limited data access. You can also purchase plans that include access to wireless hot spots across the country. For example, a plan including unlimited data and access to hot spots runs $100 monthly. An unlimited plan without Wi-Fi access runs $80. If you already have a $40 or higher voice plan, you pay $60.

A wireless laptop card will provide greater mobility. You can work from the road or the local coffee shop. But it isn't a magic bullet. Just as you experience dropped calls, you could run into problems with cellular Internet access. You may also be able to access the Internet by connecting your Internet-enabled cell phone to your laptop.

Contact Kim Komando at gnstech@gns.gannett.com.