Contents data transmission/reception system, contents data transmitter, contents data receiver and contents data transmission/reception method

A contents data transmission/reception system comprising a contents data transmitter for transmitting contents data, and a contents data receiver for receiving the contents data,

• wherein the contents data transmitter includes:
• a contents reproduction part for reproducing the contents data;
• a key information creation part for creating key information for encrypting the contents data;
• a contents encryption part for encrypting the contents data reproduced by the contents data reproduction part by using the key information;
• a transmitter transmission/reception part for transmitting the key information through plural signal lines to the contents data receiver and transmitting the encrypted contents data through the plural signal lines to the contents data receiver;
• and
• a transmitter control part for performing a control to transmit the encrypted contents data through the plural signal lines to the contents data receiver after the key information is transmitted by the transmitter transmission/reception part through the plural signal lines, and
• wherein the contents data receiver includes:
• a receiver transmission/reception part for receiving data transmitted from the contents data transmitter through the plural signal lines;
• a key information extraction part for extracting the key information from the data received by the receiver transmission/reception part;
• a contents decryption part for extracting the encrypted contents data from the data received by the receiver transmission/reception part and decrypting the encrypted contents data by using the key information extracted by the key information extraction part;
• an output part for outputting the contents data decrypted by the contents decryption part;
• and
• a receiver control part for performing a control to extract the key information from the data received by the receiver transmission/reception part and to decrypt the encrypted contents data received by the receiver transmission/reception part.

A contents data transmitter for transmitting contents data to a contents data receiver, comprising:

• a contents reproduction part for reproducing the contents data;
• a key information creation part for creating key information for encrypting the contents data;
• a contents encryption part for encrypting the contents data reproduced by the contents data reproduction part by using the key information created by the key information creation part;
• a transmitter transmission/reception part for transmitting the key information and the encrypted contents data through plural signal lines to the contents data receiver;
• and
• a transmitter control part for performing a control to transmit the encrypted contents data by the transmitter transmission/reception part through the plural signal lines to the contents data receiver after the key information is transmitted by the transmitter transmission/reception part through the plural signal lines.

A contents data receiver for receiving contents data transmitted by a contents data transmitter, comprising:

• a receiver transmission/reception part for receiving data transmitted by the contents data transmitter through plural signal lines;
• key information extraction part for extracting key information from the data received by the receiver transmission/reception part;
• a contents decryption part for extracting encrypted contents data from the data received by the receiver transmission/reception part and decrypting the encrypted contents data by using the key information extracted by the key information extraction part;
• an output part for outputting the contents data decrypted by the contents decryption part;
• and
• a receiver control part for performing a control to extract the key information from the data transmitted by the contents data transmitter through the plural signal lines and to decrypt the encrypted contents data transmitted by the contents data transmitter through the plural signal lines by using the key information.

A contents data transmission/reception method for transmitting and receiving contents data between a contents data transmitter and a contents data receiver, comprising:

• a first step of transmitting receiver ID information allocated to each contents data receiver from the contents data transmitter though plural signal lines to the contents data receiver;
• a second step of checking the receiver ID information transmitted from the contents data transmitter through the plural signal lines against receiver ID information included in the contents data receiver and transmitting, in a case where these pieces of receiver ID information are coincident with each other, information indicating coincidence of the receiver ID information from the contents data receiver through a single signal line to the contents data transmitter;
• a third step of, in a case where the information indicating the coincidence of the receiver ID information is received from the contents data receiver, transmitting key information encrypting the contents data from the contents data transmitter through the plural signal lines to the contents data receiver;
• a fourth step of, when the key information is extracted from data transmitted from the contents data transmitter, transmitting information indicating reception of the key information from the contents data receiver through the single signal line to the contents data transmitter;
• and
• a fifth step of, when the information indicating the reception of the key information is received from the contents data receiver, transmitting encrypted contents data from the contents data transmitter through the plural signal lines to the contents data receiver.