| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a pay television system which makes it difficult to use a slave decoder when it is not used near a master decoder. SOLUTION: A master decoder 1 and at least one slave decoder 2 and 3 which are separately provided with a smart card are used in one dwelling house. A central entitlement management device 13 supplies a message (EMM) for the master decoder that is protected by an enciphering means. The message is usable only with the decoder 1 and also includes data (SL1/EMM,..., SLn/ EMM) that are related to the address of the decoder 1 and the entitlement about the decoders 2 and 3. A user must inserts a subordinate card into the decoder 1 when the decoder 1 writes subordinate entitlement data on the subordinate card.</p> |
