* Seamless global roaming: illusion or reality?
An announcement AT&T Wireless made last week took me back to the Personal Communications Service wars of the mid-1990s.
Back then, the fur flew fast and furious over whether the U.S. carriers should build their digital networks – to operate in their newly won 1800-1900 MHz PCS spectrum – using TDMA, GSM, or CDMA technology.
The reason I’m reminded of the PCS tumult is the global nature of AT&T Wireless’ announcement. The carrier is now offering tri-band wireless modem cards for laptops – the Sony Ericsson GC-83 EDGE/GPRS PC Modem Card -allowing them to operate in a number of countries around the world that run GSM-based networks. The modem also supports 850 MHz analog cellular connections.
GSM was the technology standard adopted by most of the world nearly a decade ago, while North America trifurcated, then bifurcated into GSM and CDMA. As a result, there have been wireless islands of interoperability. Those on GSM networks haven’t enjoyed the speeds and efficiencies of CDMA. But when they leave the country, their phones usually work. And many wistfully wonder why Europeans seem to enjoy a level wireless ease when roaming that Americans do not.
According to AT&T Wireless, its EDGE service (which generally operates at about 100K to 130K bit/sec and bursts to about 200K bit/sec) is available in 7,500 U.S. cities and towns and in parts of Brazil, Canada, Chile, Finland, Hong Kong, Israel, Italy, Mexico, Puerto Rico and other countries. Where EDGE is not yet available, says AT&T, the modem operates at GPRS speeds (20K to 40K bit/sec) in more than 50 countries.
According to AT&T, you can get the modem for free if you sign on for the carrier’s all-u-can-eat mobile Internet service, about $80 a month, a typical price for comparable services.
GSM-based networks have long afforded users the ubiquity that CDMA-based technologies have not. Theoretically, some day none of this will matter. All the various networks in all stages of development are on a collision course to the same 3G network that is inherently CDMA-based (though it may take many years to get there and other types of networks may come along to derail 3G in the meantime).
There is a fine line between healthy competition and letting technology wars devalue networks, which, the more people they seamlessly reach, the more useful they become. The disjointed nature of the networks that grew up on disparate GSM- and CDMA-based technologies did hurt progress with interoperability and, thus, high-speed networking.
