(1.The 6th Research Institute of China Electronics Corporation,，Beijing 100083,，China； 2.Intelligence Technology of CEC Co.,，Ltd.,，Beijing 102209，China)
Abstract： With the development of science and technology and the progress of society, the industrial control systems and the Internet are increasingly integrated, and the communication security risks faced by the industrial control systems have become increasingly prominent. This paper aims at the frequent occurrence of the industrial control systems communication security events, taking PLC control system as an example, analyzes the upper and lower computers of the PLC control system, suah as system structure, communication security risks. The scheme is designed from the aspects of communication protocol selection, secure connection establishment, transmission data encryption method, and communication process, etc,，and finally a secure and confidential communication scheme based on SCTP protocol is proposed.
Key words : PLC-system,；industrial computer and controller；secure communication
