An information processing apparatus and an information processing method are
capable
of preventing information from being copied illegally.
To put it in detail, a hash function and a service key are stored in advance
in
an EEPROM of a DVD player serving as a source. In an EEPROM 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 ID with the
service key to generate a license key (=hash (IDservice_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.