chapter head
4.In chapter 3, based on ASI (asynchronous serial transport), the theory of ASI and the realize of input interface in head-end TS package processor are presented.
5.Chapter 4 discusses the SmartCOS-XC and gives the design and implementing of a smart card file system framework. Based on this, this paper gives a simulation of head-end encryption of Entitlement Control Message (ECM) and Entitlement Management Message (EMM), and implements the decryption of ECM and EMM in the smart card.

