Patent ID: 7515712

Claim:
In a terminal of a conditional access system in which a user selects a service associated with a frequency, the terminal having a tuner and a secure element with at least one authorized entitlement unit number stored therein, a method of determining whether the terminal is authorized to receive the selected service, the method comprising the steps of: receiving at least one encrypted entitlement control message corresponding to the service, wherein each entitlement control message includes a packet identifier (PID) and a payload; decrypting each of the at least one encrypted entitlement control messages in the secure element, each decrypted entitlement control message revealing at least one first entitlement unit number associated with the selected service and at least one control word associated with the selected service, wherein the at least one first entitlement unit number and the at least one control word are carried in the payload; and determining that the terminal is authorized to receive the selected service when the at least one first entitlement unit number of any decrypted entitlement control message corresponds to an authorized entitlement unit number, wherein the authorized entitlement unit number indicates a group of services that a receiver is authorized to receive; and wherein the method further comprises initial steps of: receiving over a permanently available data link an unencrypted entitlement unit table, the unencrypted entitlement unit table associating the selected service with at least one second entitlement unit number; and tuning the tuner of the terminal to the frequency associated with the selected service when any of said at least one second entitlement number represents any number of said at least one authorized entitlement unit number.