Patent ID: 7747016

Claim:
An AV contents transmitting method for transmitting encrypted AV contents to a plurality of AV contents reception apparatuses over a transmission line, the plurality of AV contents reception apparatuses including a first AV contents reception apparatus compatible with first and second encryption methods and a second AV contents reception apparatus compatible with the second encryption method and incompatible with the first encryption method, the AV contents transmitting method comprising the steps of: encrypting AV contents using the first encryption method, said step of encrypting being executed in an AV contents transmission apparatus; transmitting the AV contents encrypted using the first encryption method over the transmission line to the first AV contents reception apparatus; receiving an authentication request from the second AV contents reception apparatus; and switching the encryption of the AV contents from the first encryption method to the second encryption method, said step of switching being executed in the AV contents transmission apparatus.