Patent ID: 7266198

Claim:
A method for providing authorized access to content, comprising the steps of: receiving a PPV access request for content from a plurality of PPV users; responsive to the PPV access request, providing an asymmetric key pair having a public encryption key and a private encryption key to each of the plurality of PPV users; providing a unique device unit key for each of the plurality of PPV users, wherein each of the device unit key is encrypted with the public encryption key associated with the each PPV user; providing a first entitlement control message (ECM) for the PPV access request, the step of providing the first ECM includes, a) providing PPV access rules for the PPV access request in the first ECM; b) providing a first message authentication code (MAC) for at least the PPV access rules in the first ECM; and c) providing the first ECM as a group-addressed, multicast ECM to the plurality of PPV users; and furthermore, providing a second ECM for the PPV access request, wherein the step of providing the second ECM includes, a) encrypting a first copy of a program key with the device unit key, the program key is operable for decrypting the content for the PPV access request and deriving the first MAC; and b) providing the first copy of the program key in the second ECM.