Broadcast reception device and contract management device using common master key in conditional access broadcast system

A broadcast reception method, comprising:

• storing a master key commonly provided with respect to a plurality of broadcast reception devices and one reception device ID uniquely assigned to said broadcast reception device;
• receiving encrypted contents information delivered from a broadcast station by broadcast;
• decrypting encrypted reception contract information using the master key and the encrypted contents information using a channel key, the encrypted reception contract information being received from the broadcast station and containing at least a contract information for controlling decryption of the encrypted contents information and a reception device ID in correspondence;
• and
• selectively acquiring one contract information corresponding to a reception device ID that coincides with said one reception device ID, from the encrypted reception contract information that is decrypted, and controlling whether or not to give the channel key to the decrypting operation according to said one contract information.