A method for controlling and tracking access to disseminated information
involves encrypting data using a key that is maintained in a key
repository. A user requests a message ID and key from the key repository.
The key repository issues a message ID and key to the user. The user
generates an encrypted message using the key. The encrypted message is
then distributed with the message ID to one or more recipients. To read
the encrypted message, a particular recipient obtains the key for the
message from the key repository by providing the message ID to the key
repository. The particular recipient then decrypts the message using the
key provided by the key repository. Messages are deleted, in the sense of
becoming unusable, by deleting the corresponding key from the key
repository. A log is provided to track key repository activity including
the issuance of keys and key requests from message recipients. A policy
manager is employed to control which recipients are granted keys to read
messages and which messages are deleted.