An information processing apparatus and an information processing method capable of preventing information from being copied illegally. where a hash function and a service key are stored in advance in an EEPROM of a DVD player serving as a source. In an BEPROM of a personal computer (PC) serving as a sink, on the other hand, its ID and a license key are stored beforehand. The DVD player requests the PC to transmit the ID. The DVD player then applies the hash function to data resulting from concatenation of the lID with the service key to generate a license key (=hash (ID .parallel.service_key)). Subsequently, the DVD player generates a source side common session key and encrypts the session key by using the generated license key. Then, the DVD player transmits the encrypted source side common session key to the PC. The PC decrypts the encrypted source side common session key by using the license key stored in its EEPROM to produce a sink side common session key which has a value equal to that of the source side common session key.