Unisys has come up with an encryption-based method that lets "communities of interest" using Windows securely share data based on group policies.

The Unisys Stealth software for Windows desktops and servers makes use of session-specific encryption keys to take data and scramble it, primarily through the US government-approved Advanced Encryption Algorithm.

Users are placed into communities of interest through a group policy using Microsoft Active Directory, says Dave Gardiner, Unisys director of security technology and solution.

"The secure parser we use, which is from a partner company Security First, creates brand-new keys for each session specifically," Gardiner says. Stealth works to "bit-split" data into multiple packets and re-assemble it for delivery to authorised users, who alone can decrypt them.

Also part of Stealth is a hardware module for a Dell server, which establishes the right to use Stealth and also acts as a gateway to decrypt the scrambled data to send outside the Stealth-based network, if need be.

Unisys spent a number of years devising the Stealth security product with a particular eye on meeting the security challenges faced by the Department of Defense, which continues to use separate networks for sensitive and unclassified data, Gardiner says.

"In the DoD, some people have three or four PCs on their desktop," Gardiner says, adding Stealth is designed to retain the security-classifications concept without requiring separate networks. However, Stealth, priced at about $300 (approx £203) per user, could also be used by enterprises with similar high-security requirements.