Trials of the service began in April, and a limited commercial service will kick off this month. The initial service covers a single area in downtown Seoul, three areas south of the Han River in the city’s IT valley, and the suburb of Bundang. A subway line and two expressways from Seoul to Bundang also have coverage.
KT’s WiBro Bus
About 150 base stations support the service now, and this is expected to expand to between 700 and 1,000 by the fourth quarter this year. At that time, the full commercial service will launch in Seoul and nine other cities, according to KT’s plans.
KT says the service should deliver up to 1Mbps to users travelling as fast as 120 kilometers per hour (75 miles per hour). So, does it live up to this promise?
KT’s WiBro Bus 
To demonstrate the service and prove it works while on the move, KT took reporters on a ride through Seoul in a bus equipped with WiBro-linked laptop PCs and PDAs.
The speed challenge was difficult to test in Seoul’s congested streets—we were lucky to reach even 30 kph—but the data throughput was much easier to gauge.
The system managed to cope with streaming from Google Video just fine, and browsing the Web was easy. KT demonstrated a three-way video conference with one participant on the bus, one in Seoul and one in Australia, and that went well and worked simultaneously with Web browsing and watching a live stream of CNN.
A broadband speed-testing website estimated the connection at about 322Kbps, although the site was U.S.-based, so there could have been some impact from the international connection.
There were few glitches, and the trial service seemed to fulfill its promise of being slower than existing wireless LAN systems but with much greater coverage.
If KT and SK Telecom, which is also planning to launch a service, can deliver that for a cheap, flat monthly fee, they could provide an attractive consumer alternative third-generation data service. They offer similar data rates but are relatively expensive.