A team of computer scientists from several universities has devised an attack that is capable of reconstructing the so-called vanishing data objects created by a system called Vanish. The Vanish system was created by researchers at the University of Washington and debuted in July. Its purpose is to enable users to make sure that every copy of a given piece of data is unusable after a given period of time. The system accomplishes this by encrypting a data object with a key which is then split it into a number of pieces and stored in a large peer-to-peer network. In order to decrypt the object, a set number of the key pieces need to be reassembled.
Source: https://threatpost.com/researchers-show-break-secure-data-storage-system-092909/72262/