Patent ID: 8793502

Claim:
A method for evaluating a user's rights stored in a security module associated to a multimedia unit, the multimedia unit comprising a receiver configured to receive broadcast encrypted digital data of program services, and a central access control module having a memory, the method comprising steps of: receiving by said central access control module at least one encrypted control message containing at least one access condition and at least one control word; storing in the memory of the central access control module a copy of a user's rights table stored in the security module; storing in the memory of the central access control module a services information table comprising at least one access condition and service descriptors for said program services; receiving by the central access control module a selection of a program from a program guide displayed to a user by the multimedia unit, the program guide being based on the services information table; determining, by the central access control module, using the services information table at least one access condition associated to the selected program; searching, by the access control module, the rights table stored in the memory of the central access control module for a right corresponding to the at least one access condition associated to the selected program; when a right corresponding to the at least one access condition is found in the rights table stored in the memory of the central access control module, transmitting by the central access control module to the security module an index of the right corresponding to the at least one access condition, wherein the right defines at least a period of access to services or programs, a number of authorized accesses, possibilities of recording and/or copying content and wherein the access condition determines the index corresponding to a list of services or programs for which a right is attributed to and defined by a description comprising at least a service or program identifier, temporal data of validity of access to the services or programs; decrypting, by the security module, the control message and extracting the access condition included in the control message; verifying the rights present in the security module by using the index to locate, in the rights table of said security module, the right designated by the index; and returning a decrypted control word from the control message to the multimedia unit if the verification is successful.