Defense picks two for PKI

Defense Department officials selected two companies to provide digital certificate validation for the department's public-key infrastructure (PKI), a decision that some officials feel could spur a faster move to paperless e-government.

After a yearlong, worldwide pilot test, military officials chose Tumbleweed Communications and CoreStreet as the two certificate validation providers for its Identity Protection and Management Program, which includes the Common Access Card smart card program.

DOD requires that all e-mail messages be digitally signed, which means PKI users must download a Certificate Revocation List (CRL) that is currently a 30M file. With names constantly being added to the list, users would have to download that file at least daily to make sure the digital signatures on e-mail messages were allowed.

That might be feasible for land-based sites, said John Hines, director of Tumbleweed's validation authority product development, but it's practically impossible for ships at sea, where users share relatively low-bandwidth pipes.

Tumbleweed and CoreStreet get around the download requirement by setting up a middleman, which forwards a request for a signature validation posted by the PKI user to a CRL, collects the response and prompts the desktop application to accept or reject the e-mail.

This all takes place in a fraction of a second, and the request and response files are typically only 1K in size.

"This is an essential step to getting a real return on investment for government PKIs," Hines said. "A lot of applications have evolved to where, with a well deployed PKI, you can at last do real, paperless e-commerce."

Robinson is a freelance journalist based in Portland, Ore. He can be reached at hullite@mindspring.com.