Patent ID: 8483390

Claim:
A content distribution method with broadcast encryption, comprising: executing a setup process by a server presiding at the content distributor, the setup process comprising: generating public domain parameters, the public domain parameters comprising at least total number of content receiving clients in a distribution network; generating a server secret; and generating one or more client private keys, one for each content receiving client in the distribution network; executing an encryption process by a server presiding at the content distributor, the encryption process comprising: generating a cipher text using the server secret, a subscriber set, and a randomness, the cipher text being constant and independent of total number of content receiving clients in a distribution network; generating a plain text using the server secret and the randomness; encrypting an original content into an encrypted content using the plain text; distributing the client private keys to the content receiving clients in the distribution network; distributing the cipher text to the content receiving clients in the distribution network; broadcasting the encrypted content through a distribution network to the content receiving clients; and executing a decryption process on the encrypted content by each of the content receiving clients in the distribution network; wherein the subscriber set being a subset of all the content receiving clients in the distribution network and only those content receiving clients in the subscriber set can decrypt the encrypted content into the original content.