Design and implementation of data encryption for networked control systems

Control systems are widely used in daily life and support various important infrastructure, such as power, hydraulics, petrochemicals, transport, telecom, etc. Once the control system is attacked, the consequence would be unthinkable. The DES (Data Encryption Standard) encryption algorithm is open, and it has the merit of large encryption strength and fast computational speed. This paper describes the DES algorithm, the hardware and software design of the DES hardware encryption system based on the DES encryption algorithm and FPGA (Field Programmable Gate Array). The hardware design includes the design program of the DES hardware encryption system, the design of S-box and the design of circuit architecture. The software design is mainly to write a s-function of the DES hardware interface. An experiment of a networked DC motor speed control based on DES is described, and this networked control system has the function of hardware encryption.