Secure Transmission Technique In Military Information System

In this thesis, we deeply research on secure transmission technique in military information system and presented a multipurpose image watermarking algorithm together with a new authentication and key exchange protocol. They can be well used in the transmission platform. The research contents in this thesis include the following three aspects:(1) Research on the techniques of secure transmission platform. A transmission platform is designed and implemented for a special military communication system, according to the requirements of military secure communication system. This platform utilizes several techniques, including cryptographic algorithms, one-way hash function, digital certification, secure protocol, watermarkng and etc. Based on this platform, a new authentication and key exchange protocol is presented and has been well applied to this transmission platform.(2) Research on image watermarking. A multipurpose image watermarking algorithm is presented according to the transmission requirements of military secure communication system to digital images. This algorithm has two purposes: copyright protection and tamper detection. We embed copyright watermark utilizing variance modulation on DC coefficients of DCT transform; and in the spatial domain, we embed authentication watermark gemerated from one-way hash function, lossless compression and least-significant-bit embedding. This algorithm has been applied to the image data transmission applications of the platform.(3) Research on the attack and evaluation mechanism. An attack platform is designed and implemented to measure and evaluate the security of the present transmission platform. This platform attacks separately on the data, video and image transmission and the attack result shows that this transmission platform has a good anti-attack ability. We select Rubin logic to formally analyze the authentication and key exchange protocol designed for this transmission platform utilized, and the analysis result indicates that this authentication and key...