Cisco, Microsoft and EMC are set to build a system that lets the US government securely share data among its agencies. The US government has been looking for such a system since the September 2001 terrorist attacks.

The Sisa (Secure Information Sharing Infrastructure) project will create a system that allows data to be shared between the agencies, ensuring only the people who are authorised to access data are able to do so.

A report released in 2004 by the 9/11 Commission, which investigated the terrorist attacks, found that US intelligence agencies had cumbersome information-sharing practices that hampered their ability to counter terrorism.

The Sisa website gave scenarios of how the SISA system might be used. In one, a law enforcement agency raids an apartment and finds documents and financial ledgers in a foreign language. The material could be posted on an information-sharing site to be viewed by an investigator in another country.

The companies also gave a general view of how a person would be authenticated and access information from the network. A SISA administrator at a command center will access a user's profile in Microsoft's Active Directory, then establish a VPN (virtual private network) to let the user access the files they are permitted to view.

Cisco Security Agent governs the user's access to specific resources, such as write capabilities or a USB device, and the contents of emails and documents are protected with Liquid Machines and Microsoft's RMS (Rights Management Services).

Participating are Liquid Machines on content protection, Swan Island Networks on information-sharing architectures and Titus Labs on information labelling and classification. The business alliance between the companies will be managed by Addx.

Cisco, Microsoft and EMC will provide commercial, off-the-shelf products, with smaller vendors contributing specific technologies. Cisco will focus on secure networks and data protection, Microsoft on identity management and OSes, and EMC on storage.

The companies didn't provide a timetable or cost for the system, and government representatives weren't available early Tuesday.

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