Design of an IPTV Conditional Access System Supporting Multiple-Services

Conditional Access (CA) is typically used by pay-television operators to restrict access to content to authorized subscribers. While several commercial CA solutions exist for structured broadcasting, Internet-based television, and video-on-demand services, these solutions are mostly proprietary. Use of proprietary solutions incurs royalty payments and increased cost of components for Set-Top-Box manufacturers. In many developing countries Set-Top-Boxes for the migration to Digital Television will be subsidized by government. An efficient, flexible, and open conditional system that does not incur royalties or require specialised security hardware would be beneficial for these countries. In this chapter, the authors explore conditional access solutions that draw on the area of cryptographic key management and distribution for IPTV environments. They wrap up with propositions on how an open Cryptographic Access Control (CAC) system can be implemented practically by pay-television operators who have to handle a large number of subscriptions.

The Principle of Conditional Access System and the Realization of Set-Top Boxes

Digital TV refers to a system which transforms the traditional analog signal into digital for processing, transmitting and receiving. In order to protect the interests of the operators and ensure the development of digital television, CAS (Conditional Access System) of digital TV uses various kinds of digital technology through the scrambling process of the program, so that only the authorized users can watch the scrambled programs. This paper mainly introduces the principle of CAS in current DTV, as well as elaborates the realization example of the CA running on the STi5105 chip platform and the detailed process from transplant to descrambling successfully.