It doesn't take a visitor long to notice that South Koreans have some of the best telecommunications in the world. Cellphones work flawlessly, even in the depths of Seoul's subway system. Head-phoned teenagers hunch over virtual battlefields displayed on multimedia PCs in cramped Internet game rooms known as "baangs," which are themselves tethered to the Net by optical fiber. Meanwhile, at more laid-back cafés, open laptops are the norm, as fast Wi-Fi signals share the air with the fragrant scent of fresh-brewed coffee.

It's hard to imagine South Korea needing even more connectivity. Yet the republic is making a collective bet that it does. Even as leading carriers like SK Telecom, in Seoul, are investing heavily to improve data rates on their cellular networks, which already are state of the art, the government—with the full support of the nation's wireless providers and equipment makers—has pushed a competing technology called "wireless broadband," or WiBro for short.

A mobile version of regular broadband—take a DSL modem, cut its copper umbilical cord, and put it on wheels—WiBro is fundamentally similar to the standard known as WiMax, which is being developed by the IEEE 802.16 working group [see News, "WiMax and Wi-Fi: Separate and Unequal," IEEE Spectrum, March 2004]. But WiBro allows the user to work a spreadsheet or watch a movie while trucking along at near-highway speeds, whereas WiMax users must stay put [see photo, "Online, On the Move"].

WiBro promises much higher data rates than you can get even from a third-generation (3G) cellular system—an initial rate of 1 to 3 megabits per second, versus the 384 kilobits per second typical in advanced mobile phone networks today. And the WiBro download rate may eventually rise to about 18 Mb/s, fast enough for even high-definition television, as well as voice, video, and old-fashioned e-mail and Web traffic.

On the other hand, while even the most sophisticated mobile phone networks are still customized mainly for voice, WiBro handles strictly data. It can carry voice traffic, but only by chopping it up into data packets and using voice over Internet Protocol. (VoIP is increasingly seen in wire-line telephony but has yet to be deployed on cellular systems.)

Betting that many of its mobile data-services customers will not be content for long with mere 3G speeds, SK Telecom plans to establish WiBro service in South Korea's major cities. Users, as they roam, will be able to toggle between WiBro and 3G, says Joo Sik Lee, vice president of the company's Network R&D Center, in Seoul. Thus, bored bus and subway commuters will be able to tune in to their favorite radio stations, watch on-demand movies, and play games online.

The Korean government has already set license fees and issued guidelines for commercial WiBro services, which it says it wants to see up and running by mid-2006. If that goal is met, it will cap six years of rapid development—among the slow boats of telecommunications standards, WiBro will be a speedboat.

WiBro may meet its deadline. South Korean cellular companies have already done extensive feasibility testing. SK Telecom, the country's largest cellular provider, and equipment maker LG Electronics Inc. chose technology from Adaptix Inc., in Seattle. Samsung Electronics, KT (Korea Telecom), and the Electronics and Telecommunications Research Institute, in Daejeon, went with Navini Networks Inc., in Richardson, Texas.

Navini descends from an Austin, Texas­based company, Cwill Telecommunications Inc., which developed 3G systems; Adaptix traces its lineage to a company founded by Hui Liu, who pioneered WiBro technology at the University of Washington. Hui once worked for Cwill and now serves as chief technologist for Adaptix.

Still, there are two obstacles in WiBro's way before it can safely come into port. First, there is the matter of certification: WiBro's backers would very much like to get it recognized by the IEEE 802.16 committee as the mobile version of WiMax, which could happen as early as this fall. Support from Intel Corp., which lately has thrown its weight behind fixed WiMax, will probably be crucial.

Even then, for WiBro to have much chance of venturing out beyond the Korean peninsula, a variety of compliance and interoperability standards will have to be reconciled. That means the rest of the world is not likely to see WiBro systems in place until late 2007, says Dave Sumi, vice president of marketing for TeleCIS Wireless Inc., in Santa Clara, Calif., a developer of both fixed WiMax and WiBro chip sets.

The second hurdle is the marketplace itself. Sumi, arguing that "superior technology will always win out in the end," points out that "for data, 3G equipment isn't nearly as efficient on a dollars-per-kilobit basis," besides being much slower than WiBro.

But however inferior 3G networks may be, carriers around the world, from NTT DoCoMo Inc. in Japan to Verizon in the United States, have spent billions of dollars building them.

"The Verizons of the world have already placed their bets," concedes Vern Fotheringham, CEO of Adaptix.

The expense of acquiring licenses and of installing the base stations for WiBro is onerous, as the South Korean government learned in March, when LG Telecom, the republic's third-largest cellular provider, decided not to apply for a WiBro license. (LG Telecom is a distinct company from LG Electronics, an equipment and device manufacturer that still plans to make WiBro hardware.)

A shocked South Korean Ministry of Information and Communication, which thought it was running a competition among four companies vying for three licenses, instead was left to simply bless the three remaining ones: SK Telecom, KT, and Hanaro Telecom.

Then, on 26 April, the weight of the WiBro burden became further evident when Hanaro dropped out by deciding not to meet the first licensing requirement—a US $116 million payment due on 1 May.

There are, though, a handful of large wire-line telcos without cellular networks. Some, such as China Telecom, may find establishment of a WiBro network an attractive alternative.

Additionally, a major Internet service provider without a physical network of its own, such as EarthLink or AOL Broadband, could go for WiBro. In January, for example, SK Telecom and EarthLink announced a partnership that could eventually bring WiBro service to EarthLink's 5 million U.S. customers.