In Brief

All three major 3G cellular laptop data networks in the U.S. (Cingular, Sprint, Verizon) charge the same price: $79.99 per month for unlimited data contracts, or $59.99 if you have a voice plan as well. And all operate at the same basic download speeds: 400-700 Kbps. What differentiates the plans is coverage, technology, software, and support.

Cingular's 3G data card entry, the Sierra Wireless AirCard 860, scores high on all four of those parameters, although with an asterisk in the coverage column. Cingular's 3G HSDPA network is only just rolling out across the U.S., and may not yet be available in your area. However, Cingular's 2.5G U.S. EDGE coverage can't be beat, so you can use that while you wait for HSDPA. Furthermore, since HSDPA is based on GSM, it has the major benefit of global roaming, which Sprint and Verizon can't offer with EV-DO. The Sierra Wireless card is quad-band, so it supports roaming on European and Asian GPRS/EDGE networks, although not UMTS.

Cingular's new GlobalConnect plan is designed to take advantage of that capability. The roaming plan (to debut later this month) will feature unlimited domestic data usage on HSDPA and EDGE networks plus 100MB of data throughout Asia and Europe for one price of $139.99 per month. There's also a U.S./Canada/Mexico plan for $109.99. About 25 countries will be in the plan initially, with more to be added as 3G service ramps up across the globe.

If you're a world traveler, or simply a domestic Cingular subscriber who can take advantage of the voice plan discount, the Sierra AirCard 860 is an excellent choice for 3G data. The Cingular Communication Manager software for Windows is full of useful features like Wi-Fi connection integration and SMS messaging, and connections are very strong. Mac users will have to wait for software support, or go through torturous manual modem setup procedures.

In Depth

The AirCard 860 is a compact PC Card with zero protuberance from the edge of your laptop, aside from the tall, jointed antenna.

The antenna pops out, so you can leave the card in your laptop when it's stowed in a bag, and just find a place to keep the antenna. The card also has a port for higher-power external antennas, which can be useful in low-signal environments or mobile applications. One time we experienced severe signal acquisitions problems, however, and thought there was something wrong, but it turned out the antenna was not quite pushed all the way in.

Installing the card was simple, and the Communication Manager opened up and found a 3G signal straight away. We simply clicked Connect, and got online. Using CNET's Bandwidth Meter throughput test, we got a full 384Kbps on downloads even with only two bars of signal strength. At four bars, we occasionally got more than 1Mbps, and most of the time we got in the 500s with a three-bar signal. Cingular's claim of 400 to 700 Kbps in real-world throughput is quite reasonable. The card is rated up to 1.8Mbps for downloads and 384Kbps for uploads, so there is room for future network upgrades.

To test range, we drove literally all the way around the SF Bay Area, in a circle from Berkeley to San Francisco to San Jose and Oakland. During the approximately 100-mile trip, we lost connection only three times, and only for a brief period each time, an impressive feat for a brand-new network. Bars of signal strength also rarely dropped below two during the trip, although sometimes we were switched to 2.5G EDGE service, which runs about 150Kbps

The Communication Manager also supports SMS and email messaging right within the application, and has support for VPN networks. Built-in acceleration technology reduces picture quality on Web pages to speed surfing. The level of picture compression is adjustable. You can also set options like whether to allow international roaming, and perform firmware and driver updates within the client. But our favorite feature is the ability to manage both cellular and Wi-Fi connections in one place, so you aren't constantly having to turn Wi-Fi on and off elsewhere when you initiate a cellular connection. You don't have to use it, but we did for our testing.

To switch to Wi-Fi, you just click on the Wi-Fi tab and go. We used the Rules settings and network profiles to configure the card to automatically connect to our chosen Wi-Fi networks when available, and to switch from cellular to Wi-Fi when in range of those networks.

Another handy feature in the software is the ability to turn either the Wi-Fi or cellular radios on and off with a click. This can save a lot of battery power when traveling, and turning off Wi-Fi when not in use is also advisable from a security point of view.

Overall, the Cingular AirCard 860 is a top-notch card with excellent software and support. The Wi-Fi integration is a nice bonus. As Cingular ramps up its 3G HSDPA network, it can only increase in attractiveness. We just wish there was a Mac version of the Communication Manager as well.