Research On End To End Encryption Terminal In Mobile Communications System

The transmission of digital signals in mobile communications system goes through airspace, base station, and switch equipments which suffer from a lot of security problems and are not considered as secure enough. However, the existent security measures in present mobile communications system cannot keep the mobile communication secure. As a result, mobile communication is limited in a high security level.End to end encryption can be used to overcome these problems: through end to end encryption, the info between mobile terminals is encrypted to cipher text in the whole transmission process against various attacks. Moreover, end to end encryption does not need to update the fundamental equipment in mobile communications system.Nowadays, there are some end to end encryption systems for mobile communications in developed countries. However, many weaknesses exist in these systems: the low quality of voice, the need of special encryption mobile terminal, and some security weaknesses. These problems relate authentication, encrypting/decrypting, coding/decoding of voice, and transmission of cipher signals, which are all implemented in encryption mobile terminal. Thus, a research on end to end encryption mobile terminal is urgent.In this paper, the security techniques on end to end encryption mobile terminal are systematically studied, which concludes the analysis on the security characters of encryption terminal, the research about ciphertext transmission model, authentication and cryptography schemes, the design of the encryption terminal and its implementation. The main works and achievements are described as follows:1. Research on the security problems of mobile encryption terminal itself: hierarchically discuss the security problems and techniques of encryption terminal itself. 2. Research on the transmission models: analyze various channels, and design the end to end encryption transmission models in mobile communication system.3. Research on the authentication mechanisms regarding encryption terminal: based on the analysis the problems existed in present authentication schemes, propose two novel mutual authentication schemes which are more secure and have higher efficiency, and analyze these proposed schemes in security, efficiency, and functionality.4. Research on the end to end voice encryption mechanism: considering the special characters of mobile encryption terminal, design the end to end voice encryption mechanism which concludes the encryption algorithm, the working modes, and the key management.5. Design and Implementation of the encryption terminal: design and implement an encryption terminal, and analyze the encryption terminal in details.