Universities Spar Over Disappearing Electronic Messages
Found on The New York Times on Monday, 21 September 2009
In less than two months after a group of University of Washington computer researchers proposed a novel system for making electronic messages "disappear" after a certain period of time, a rival group of researchers based at the University of Texas at Austin, Princeton, and the University of Michigan, has claimed to have undermined the scheme.
"In our experiments with Unvanish, we have shown that it is possible to make Vanish messages "reappear" long after they should have "disappeared" nearly 100 percent of the time," the researchers wrote on a Web site that describes their experiment.
There's a fundamental flaw: transporting a decryption key over an untrusted public network and relying on the integrity of all members. Partial keys might be deleted over the time by Vanish, but it cannot be avoided that someone just saves all Vanish related traffic. That data dump will exists as long as the admin wants to keep it.