Investigations on smart card-based secure protocols for autenticated key establishment in Digital pay-TV systems

Interactive TV is a promising technique to realize individualized services besides traditional video broadcasting, such as VOD (video on demand), email on DTV (digital TV), e-banking. Utilizing return channel (like Internet, mobile communication), many new applications can be established, which promote the value-added services of DTV. For more profound applications, security mechanisms must be deployed to protect the profits of both the content providers and subscribers. This paper presents investigations on the smart card-based secure protocol for user-STB authentication and session key establishment in DTV system. The proposed secure protocol has features of bidirectional authentication, session key secrecy, session key confirmation, forward security, and efficient interval restart, etc. Therefore, the protocol is appropriate for use on secure conditional access and can be referenced easily in future CA systems for value-added applications.