一种免智能卡的有线电视条件接收技术的研究

Research on Conditional Access Technique for Cable TV Based on Cardless Model

传统有线电视CA(Conditional Access,条件接收)系统通过前端发送加密的ECM(Entitle Control Message,授权控制信息)和EMM(Entitle Management Message,授权管理信息)实现用户授权信息的加密,接收端机顶盒利用智能卡进行数据的解密,实现用户授权的控制。本文提出了一种基于DES(Data Encryption Standard)加密技术无需智能卡的LCA(Lo-cal Conditional Access,局域条件接收)系统的结构模型,该模型中前端管理服务器通过EMM发送用户的授权信息、ECW(Encrypt Control Word,加扰控制字)和Email等信息,接收端机顶盒通过解析EMM信息对用户进行授权控制。

In the traditional digital cable TV CA （ Conditional Access） system, the encryption of user entitle information, which is transmitted by head-end system, is archived by the encrypted ECM （Entitle Control Message） and EMM （Entitle Management Message）, and the decryption of the encrypted data in the receiver side, is completed by the smart card which is integrated in the Set-Top-Box. This paper proposes a new model of cardless LCA（ Local Conditional Access） system based on DES（ Data Encryp- tion Standard）. In this system, the user entitle information, ECW （Encrypt Control Word） and Email etc. are carried within EMM which is transmitted by the head-end management server, and in the Set-Top-Box side, the controlling of the entitle infor- marion is achieved by parsing the EMM information.