Microsoft is reported to be considering including its Infocard user authentication technology in the next version of Explorer.

According to Microsoft sources quoted by Network World magazine, the software could now turn up in the major version 7.0 overhaul of the browser, due out next year.

Infocard, currently in beta, is the codename for a browser-based system for keeping track of a user’s password and user name identity as they move around websites. Connecting to an Infocard server should make it possible to visit multiple sites without having to log in repeatedly.

To date, the best known example of such a system has been Microsoft’s Passport, which has always aroused privacy concerns.

However, unlike Passport, Infocard has been designed to work with software other than Microsoft’s, whether browsers or servers.

If true, the news will represent yet another acceleration in web security by Microsoft, which now appears to be completely overhauling its browser in an attempt to take back the initiative from rivals.

That hasn’t stopped the company working with other browser companies on the issue of user identity.

"We are having concrete discussions with Firefox and others about specific mechanisms that would communicate between a Web site and the browser so we can enable credential selection such as InfoCard," John Shewchuk, CTO of distributed systems at Microsoft, was quoted as saying by Network World.

Despite its open design, Microsoft still had to fend off suggestions in recent weeks that Infocard is really a repackaging of its Passport software in another form.