Verfahren zur Realisierung geschützten Zugriffs auf gemeinsame Informationen

摘要

The inventive methods employ symmetric encryption with first and second keys to provide secure access to information accessible to be shared among a dynamically changing set of authorized users on a network having a server. A single copy of the information, encrypted with the first key of the server, is stored in a location accessible to all network users. The second key is a private key of an authorized user and is used by the server to encrypt the first key. The encrypted first key is then stored by the server at a storage location accessible by the authorized user. The user accesses the storage location, obtains the encrypted first key, and uses his private second key to decrypt and thereby recover the first key. The user then decrypts the stored information using the recovered first key. $$