"There is a real desire by users to share URLs with collaborators in real time," says Meredith Ringel Morris, a computer scientist in the adaptive systems and interaction group at Microsoft Research, who launched a collaborative search tool called SearchTogether last year. A survey conducted by Morris in 2006 found that 30 percent of participants said that they had tried to browse with others using instant messaging.

Morris says that the researchers' efforts to simplify cobrowsing through RCB "are a big step in the right direction." Users with limited technical skills could especially benefit from a cobrowsing tool, Morris says, since it allows a more experienced Internet user to walk them through unfamiliar tasks. Because this needs to be easy to do, she says, it's important that RCB uses a regular Web browser.

On the other hand, Morris worries that RCB places too much of a burden on the host of a cobrowsing session. As the system is currently implemented, a user can only set up a session if she knows her computer's host name or Internet protocol (IP) address, as well as the number of an unused transmission control protocol (TCP) port.

Vladimir Estivill-Castro, a professor at the School of Information and Communication Technology at Griffith University, in Australia, who has studied the usability of cobrowsing tools, says that the approach "seems rather convenient." But he thinks that more work needs to be done to improve the system so that many users can take actions on a single Web page.

RCB is not yet available to the public, but the researchers presented their work last week at the Usenix Technical Conference, in San Diego. Wang says that his group filed a provisional patent last September with the hope of getting the technology adopted by major browser vendors.