Patent ID: 7412060

Claim:
A contents data transmission/reception system comprising a contents data transmitter transmitting contents data and a contents data receiver receiving the contents data, wherein the contents data transmitter includes: a key information selection part which generates a plurality of key information for encryption and selects a key information among a plurality of the key information; a contents encryption part which encrypts an inputted contents data by using the key information selected by the key information selection part; and a transmitter transmission/reception part which transmits a plurality of the key information, and then the encrypted contents data and a selection information regarding the key information used in the encryption of the contents data to be transmitted, wherein the key information, the encrypted contents data and the selection information are divided to be transmitted through a plurality of signal routes respectively, and the contents data receiver includes: a receiver transmission/reception part which receives a plurality of the key information, the encrypted contents data and the selection information through the plurality of signal routes, each of which are connected to the contents data transmitter; a key information storage part which stores a plurality of the received key information; a key information extraction part which extracts the key information used in the encryption of the contents data based on the selection information among a plurality of the key information stored in the key information storage part; a contents decryption part which decrypts the encrypted contents data by using the key information extracted by the key information extraction part; and an output part which outputs the contents data decrypted by the contents decryption part.