Feature: FAQ--What Are 3G Networks?

Given all the hype its recent U.S. introduction has received, 3G, a high-speed wireless data and voice network technology, seems reminiscent of 3D, the headache-inducing 1950s movie gimmick that had the masses peering at Godzilla through geeky glasses.

But what's behind the 3G hype? What exactly are 3G networks, and why should we care? Here's the scoop.

Phoning It In

The term 3G is shorthand for the third generation of wireless network technology. This technology is also sometimes referred to as the Universal Mobile Telecommunications System, or UMTS. According to proponents, "always-on" 3G networks will enable you to do all sorts of sci-fi things not possible before.

With 3G, mobile phones, handheld devices, and notebooks with 3G-compatible modems can easily handle high-speed multimedia content and serve as all-in-one communication, entertainment, and information devices, the promise goes. You'll be able to hold a videoconference with your coworkers while simultaneously surfing the Web--on your mobile phone. E-mail messages with file attachments will instantly download to your PDA or notebook. One of my favorite claims is that you'll be able to pull up to an automated car wash, activate the sudsing with your 3G phone, and have the charge added to your phone bill, according to 3GNewsroom.com.

Who knows? In the near future, actors who are routinely accused of phoning in performances may do exactly that.

From First to Third

The first generation of wireless networks, known as 1G, was a basic analog voice phone service without data capability.

With second-generation networks, or 2G, wireless technology progressed from analog to digital. These networks are still the most prevalent standard in use today. There are three main 2G network standards: CDMA (Code Division Multiple Access), GSM (Global System for Mobile Communications), and TDMA (Time Division Multiple Access). Each type has its own characteristics and features. For instance, GSM networks are global, and the mobile devices connecting to them can be used in the United States and abroad.

But 2G networks were primarily intended for digital voice services. Under ideal circumstances, 2G networks are painfully slow at sending data, reaching 10 to 19 kilobits per second, which is much less than half the speed of a traditional 56-kbps dial-up modem. And unless they've been especially optimized, most Web pages accessed from a 2G network inch across a handheld screen, which makes surfing the Web on a 2G wireless device as efficient as running underwater. To date, network service providers have had a difficult time luring the masses onto the wireless Web.

A few network providers introduced an interim standard, 2.5G technology, that can handle speeds between 56 and 144 kbps. But for several years, the big push has been toward 3G, which promises data transfer rates of 144 kbps to 2 megabits per second, and an always-on connection.

The 3G technology primarily consists of two standards, WCDMA (Wideband CDMA) and CDMA2000. With fewer competing standards, eventually 3G service should be more widely available than 2G networks have been, and roaming will be far easier, advocates say.

Beyond the Hype

The past few months have seen the first 3G networks arrive in the U.S. from such providers as Verizon Wireless, AT&T Wireless, and Sprint. So far, despite its improvements over 2G technology, 3G hasn't fully lived up to its promise. Top data transfer speeds of 2 mbps won't be available for another year or two, and early 3G network services are more likely to be 144 kbps or less.

For instance, in PC World's test of Verizon Wireless's 3G network using a notebook, average speeds in downtown San Francisco and Boston were 60 kbps and 70 kbps, respectively. Though the network's current top speed is billed as 144 kbps, average speeds are 40 to 70 kbps, depending on location, device, and network traffic.

Similarly, AT&T Wireless's 3G service has a theoretical top speed of about 115 kbps. But in our tests in Seattle on a notebook, speeds were about 38 kbps.

In addition, 3G networks aren't nearly as prevalent geographically as 2G networks, so coverage can be spotty. And service plans are often expensive and confusingly structured. Users of the Sprint PCS Vision network, for instance, are billed according to the amount of data downloaded, which can be difficult to estimate and control.

Despite 3G's current limitations, our testers concluded that the new networks are worth the price premium for mobile business users who need frequent access to e-mail and the Internet. But don't expect to use your cell phone to have your car washed just yet.

For more information on 3G networks, see the following PCWorld.com articles:

• "First 3G Networks Won't Be Fancy"
  
  
• "Samsung Shows Off Two New Palm-Based Phones"
  
  
• "Calling on Sprint's New 3G Network"
  
  
• "Connect Fast with 3G Nets"
  
  

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