An active entitlement key management for CA system on digital TV broadcasting system

In this paper, we propose an active entitlement key management scheme for CAS on digital TV broadcasting system. We introduce not only a novel concept of ARL for dynamic entitlement management, but also key distribution model based on four levels key hierarchy, and ARL transmission table for efficient transmission bandwidth consumption. With the proposed scheme, we can reduce key generation and encryption load considerably compared to passive entitlement management.