Stream Cipher Machine Design Based On FPGA

With the rapid development and wide application of communication and network, the cryptography, which aims at the information security, has become the important research fields in information science and technology. The stream cipher is one of the important branches of modern cryptography. Together with the effectively mathematical tools, the development of shift register theory has brought quite great progress of stream cipher theory. In order to seek an attack mechanism and achieve communication jamming, this paper has designed a stream cipher machine based on microcontroller and FPGA as a hardware research platform.Firstly, this paper has emphasized on discussing the linear feedback shift register. Especially, the m-sequence which is widely used at present has been discussed. The author pointed out that m-sequence has favorably random statistical characteristic, also proved that m-sequence is pseudo-random sequence in fact.Secondly, this paper has discussed the complete FPGA design flow and the problem which should pay attention to in design stream cipher algorithm, and has introduced A5algorithm and RC4algorithm, and has introduced each module within the FPGA in detail.Finally, this paper has introduced how to implement the initial key transmission with microcontroller and how to send and receive data information with E1.