Secure pay-TV for chained hotels

Abstract

There is an increasing demand of securely selling pay-TV channels to large organizations such as chained hotels. Most solutions usually employ a key generation authority to distribute secret access credentials for all users, which would cause the single-point problem of inefficient key management. Further, there is a risk of the leakage of users' access credentials while countermeasures to find out the leaked credentials are lacking. To address such issues, we propose a leakage traceable hierarchical key distribution (LTHKD) framework with the key delegation and the key-leakage tracing. The key delegation allows the key generation authority to apportion the tasks of access credential generation to a number of group authorities; the tracing mechanism provides an efficient method to find out the leaked access credentials. We present a concrete LTHKD scheme by extending hierarchical identity-based encryption to groups with users' access credentials elegantly encoded by unique fingerprint codes. We formally prove the security of the proposed scheme in a rigorous definition and conduct thorough theoretical and experimental analyses to evaluate the system performance. Surprisingly, the results show that the added key-leakage tracing mechanism has little affection on data encryption and decryption procedures.