On Self-Synchronizing Stream Cipher

Privacy protection of the information in transmission and storage is increasingly a hotspot in the process of social information. The security, integrality, availability and anti-dependency of information in network circumstance can be solved by cipher technique, the key technique of information safety.Security intensity of stream cipher algorithm has been the core study issue since the emergence of cipher technique and its theory. The key security of algorithm must be guaranteed because the algorithm of cipher of modern sequence flow was completely public. "One cipher" mechanism was proved to be no condition security by Shannon. Since the stream cipher is the same as "one cipher once", the study of stream cipher is very important in theory and application..Based on self-synchronizing stream cipher, quick software encryption of stream cipher was studied in the view of cipher coding and cipher analysis respectively. The main content includes:1. A new self-synchronizing encryption algorithm SRH-512 based on software application environment was put forward.2. With the reference of popular PC using 32bits data-bus, the traditional stream cipher using single bit was modified, and 32 bits encryption unit was used in SRH-512 algorithm to improve the software encryption effect.3. Combined action of cryptograph and part key was used in SRH-512 algorithm to get the practical encryption key, which broke the finite cycle of the sequence cipher in encryption key, made the encryption key in practical applications unpredictable, which finally enhanced safety of the encryption.Based on example analysis and experiments, the software application oriented design methods and experience methods were summarized and improved, finally, the software encryption procedure was realized.