Novell is developing an open source implementation of Microsoft's identity card technology that is functionally equivalent to the Windows software but will run on both Linux and Macintosh.

The Novell software, for which the source code is already available, provides users with a "digital wallet" that holds any number of separate identity cards that can be used to authenticate to various Web sites or network resources, such as applications or databases, or to complete transactions online.

Novell tapped into Microsoft's InfoCard technology to develop what it is calling an InfoCard Selector, a graphical user interface that lets users select cards from their digital wallet.

Novell began work on the selector last September, long before its highly publicized partnership with Microsoft in November, but the work aligns nicely with the partnership's focus on interoperability.

To support the InfoCard Selector, Novell used technology on the back end from its >Bandit project, a sort of standard bus that identity-enabled applications and identity systems can plug into, and the Higgins project, a framework designed to integrate identity, profile and relationship data from across multiple systems.

Novell plans to turn its selector software into a licensed product, but has no timetable for doing so, according to company officials.

The promise of the technology is that users will have a standard and secure way to control their identity information and determine with whom to share it.

"The big picture here is the availability of a viable cross-platform identity selector," says Dale Olds, a distinguished engineer with Novell. "For the first time we have a functionally equivalent system to Microsoft's CardSpace that runs on Linux and Mac."

CardSpace, which shipped in November with Windows Vista, is Microsoft's implementation of its own InfoCard technology.

Novell's work is further validation of the integration between user-centric identity technologies such as Microsoft's InfoCard and OpenID, which is a simple authentication protocol.

At the RSA Conference in February, Microsoft pledged to integrate OpenID with CardSpace.

Novell's work comes with the blessing of Microsoft, which has been pushing for industry-wide acceptance of its InfoCard technology.

The biggest step came in September last year when Microsoft quietly released its Open Specification Promise (OPS), which gives developers access, without need for licenses or fear of legal action, to many of the Web services protocols Microsoft has developed over the past years.

OPS includes the current versions of protocols in the WS-* security stack, which form the foundation of Microsoft's InfoCard technology and its Identity Metasystem infrastructure, an architecture to support digital identity.

Novell used the protocols within OPS to develop its open source InfoCard Selector.