| 4. | Finally , studies the instruction system of cos upon a dedicated instruction of smartcos - xc . 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 在对通用cos的研究的基础上,首先简单分析了smartcos - xc ,结合该cos ,论文针对有条件接收系统,按不同用途、不同类型分别设计并实现了存储用户授权及智能卡应用的文件体系结构,通过该cos的指令系统,设计并实现了模拟前端授权控制信息( entitlementcontrolmessage , ecm ) 、授权管理信息( entitlementmanagementmessage , emm )数据生成模块及用户端ecm 、 emm解密模块。 |