Patent ID: 8364964

Claim:
A method of registering a plurality of client devices with a device registration server for secure data communications, said method comprising: generating a unique symmetric key for each of the plurality of client devices using a cryptographic function on a private key of the device registration server and a respective public key of each of the plurality of client devices; sending a broadcast message containing the public key of the device registration server to the plurality of client devices, wherein each of the plurality of client devices is configured to generate a respective unique symmetric key from the public key of the device registration server and its own private key using a cryptographic function, and wherein each of the unique symmetric keys generated by the client devices matches the respective unique symmetric key generated by the device registration server for the respective client device; and communicating the unique symmetric keys to an entitlement management message generator (EMMG) server, wherein the EMMG server is configured to derive an encryption key from each of the unique symmetric keys for each of the plurality of client devices and to encrypt an entitlement management message for a particular client device using the encryption key for that particular client device.