CONDITIONAL ACCESS INFORMATION ARRANGEMENT

摘要

APPARATUS IN A RECEIVER, FOR PROCESSING TRANSMITTED ENTITLEMENT CONTROL INFORMATION, INCLUDES A PACKET TRANSPORT PROCESSOR (13-15, 19) FOR SELECTING SIGNAL PACKETS HAVING PAYLOADS CONTAINING A CONDITIONAL ACCESS PAYLOAD HEADER AND A REMAINING PAYLOAD OF ENTITLEMENT DATA. RESPECTIVE PAYLOAD HEADERS INCLUDE GROUPS OF BYTES WHICH ARE CODED IN A MANNER TO ALLOW OR DISALLOW THE RESPECTIVE RECEIVER FROM PROCESSING THE ENTITLEMENT DATA. A CONDITIONAL ACCESS FILTER (30) PREPROGRAMMED WITH A SUBSCRIBER SPECIFIC CONDITIONAL ACCESS CODEWORD EXAMINES RESPECTIVE BYTE GROUPINGS OF THE CONDITIONAL ACCESS HEADER FOR A MATCH WITH THE SUBSCRIBER SPECIFIC CONDITIONAL ACCESS CODEWORD. ONLY IF A MATCH OCCURS IS THE PROCESSOR PERMITTED TO PROCESS (17,18,21-24) THE ENTITLEMENT DATA. THE ENTITLEMENT DATA IS THEREAFTER UTILIZED TO GENERATE (31) DECRYPTION KEYS FOR DESCRAMBLING (16) PORTIONS OF THE TRANSMITTED SIGNAL.