CLEANING UP HIDDEN CONTENT WHILE PRESERVING PRIVACY

摘要

The present invention relates to a method of removing content from a multi¬ user device (102), and a multi-user device arranged to securely store content. A basic idea of the present invention is to enable an authorized user (101) of a secure, tamper-proof device to issue a content removal command, a "clean-up" command, for content that is stored on the device, to which authorized users of the device have no access rights or no ownership rights. When an authorized user issues a clean-up command for such content, the device checks a list (105) of users that are authorized to store content on the device. The list is maintained and stored securely by the device and comprises an identifier, in the form of e.g. a public key, of each authorized user. If none of the users on the list is associated with the content for which a removal command has been issued, the content is removed from the device.