Digital Tv Conditional Access System

With the development of the information technology,many new services havebeen provided to serve people.New technology such as digital TV become in use.Conditional Access is the process of determining which individual digitalreceivers shall be able to deliver particular broadcast programmes to end users. It isan essential part of the business of Pay Television and therefore vital to thedevelopment of successful digital television businesses.Because conditional accesssystem is very expensive,we must develop our own conditional access system.From the begining of the paper,I simply introduce status of the digital TVBroadcasting development.Then I introduce the principle of the Conditlona AccessSystem,At the end of paper,I describe my design of the interfaces.The content of this paper is as follows:Design a conditional access system adopting three-level-encryption.Realize ECM generation adopting DES algorithm and realize EMM generationadopting RSA algorithm.Realize all sending protocol of the ECM and EMM using VC++ tools.Tests of the conditional access system have been carried on,and the conditionalaccess system is usable.