Patent ID: 7406593

Claim:
A method of requesting a continuation message comprising the steps of: storing a call-up message in a user device, the call-up message being generated by a user device including: a. a tag table identifier value; b. a set of user device descriptive values, where one or more of the user device descriptive values provide information concerning a state associated with the user device; c. a nonce; and d. a hash function; and applying said hash function to the combination of said set of user device descriptive values and said nonce to provide a hash result value that conceals the user device descriptive values from a guardian center and all other devices, where the concealing of the user descriptive values protects the privacy of a user associated with the user device; processing the call-up message at the guardian center to detect use of an infringing copy of software on the user device, where the call-up message is used to prevent a tag table identifier value from being used simultaneously on multiple user devices; and requesting a continuation message for use in connection with controlling use of protected software on the user device by securely sending from the user device to the guardian center said tag table identifier value and said hash result value in a call-up message.