A pilot project testing high-speed Internet access on portions of BART will expand systemwide, allowing people to surf the Web, send e-mail and videoconference when riding the rails or waiting in the stations.

The goal is to outfit the 104 miles of track and the 43 stations by the end of 2011, said Cooper Lee, CEO of Wi-Fi Rail Inc., the startup company based in Gold River (Sacramento County) that will provide the communications system.

The 20-year deal was announced Friday.

The company began a limited experiment with the system about a year ago that involves the underground downtown San Francisco stations and a short stretch of open-air track in Hayward.

Service has been free during the demonstration project in which more than 16,000 users signed on. The company reported seamless service between the stations, even as the trains ran at high speeds.

The company will start charging for use when it completes the next phase of the project, which will include the Transbay Tube and all the subway stations in San Francisco and downtown Oakland, said Lee.

Once fully complete, subscribers will be charged about $30 a month, $9 a day, $6 for two hours and $300 for a year's subscription, Lee said. The service will be offered at reduced rates until the entire system is up and running.

BART riders in the future will be able take advantage of free Internet access - but with a catch. Access will be cut off after 3 1/2 minutes and the users will have to endure 30 seconds of ads before being able to surf the Internet.

Unlike other transit system Wi-Fi projects that rely on satellite or cellular service to operate, the BART model uses fiber-optic equipment that has the capability of handling heavier loads at faster speeds. Lee described the system as the first of its kind in the world. The company hopes to showcase BART as it pursues other markets.

"This is a unique opportunity to demonstrate what high-speed Wi-Fi access, interconnected by a huge fiber-optic backbone, can mean to a transit system and its passengers," Lee said.

BART spokesman Linton Johnson said the system will not only provide a convenience for riders, but also can be used as a backup to the agency's radio system. In addition, BART can tap into the technology to one day provide information to the public via video monitors in the stations and on the trains.

Thomas Hawk, a BART regular, tried the service during the pilot phase. "When I could get connected, I liked it," he said. But the limited range available during the demonstration and the time it took to log on was more of a hassle than it was worth, he said.

And while he likes the idea of Wi-Fi on the train, "I wouldn't be willing to pay for the service if it was systemwide. As cool of a thing as it is, I've got other things I could do with my laptop, like process photos, that don't cost me anything."

Lisa Rein, a digital librarian, has used the Wi-Fi connection during the trial period and liked it. When told of the proposed cost, her first reaction was, "That's a lot of money." But, she said, for people who spend a lot of time on the trains, the service could be "really helpful and help reduce work stress."

Neither BART nor Wi-Fi Rail representatives would provide details of the contract Friday. Johnson and Lee, however, said the company would pick up the construction and operating costs. Lee said it was crafted to give BART a share in the expected revenues.