Based On The Pollution Of The Chaotic Sequence Password And Hash Function Research

In the information age today, with the rapid development of computer and Internettechnology, people can make a very quick access to information resources. However, it is theexistence of system security vulnerabilities by open interconnection network, sharing ofinformation and network technology. so that the information there is a serious security threatin transmission and storage, information security has become the focus of academe andenterprise. The password as a key in part of information security, it is very urgent andimportant for a more secure, efficient and reliable cryptography technology.Chaos and cryptography have a natural contact structure, that makes the chaos theory’sapplication in cryptography has a very good encryption effect. At present, the report of thechaotic encryption algorithm often has some problems. for example, chaotic sequenceencryption algorithm of single chaotic mapping is easy to be cracked. therefore, a highersafety encryption algorithm proposed is needed. This paper is mainly devoted to the researchof the theory on chaos encryption algorithm and based on Hash function’s construction,further it is tried to use it in the field of information security.The following tasks have been accomplished in this thesis:The first chapter, briefly introduces the background of chaotic cryptography research,significance and research status of chaos encryption and chaos Hash function constructionalgorithm at home and abroad.The second chapter, Briefly introduces the basis of chaos theory,chaotic ciphers and thecharacteristics of the definition of chaos and chaotic motion; Judgment on the basis ofsummarized the chaos research and guidelines; Basic knowledge and the relationship betweenchaos and cryptography cryptography.The third chapter, puts forward the concept of pollution chaos dynamic system, and putsforward a kind of chaotic dynamical system based on the pollution encryption algorithm, thisalgorithm by computer simulations safety experiment analysis, analysis of experimentalresults show that the algorithm has good encryption effect, safe, practical and efficientcharacteristics, relationships between key and plaintext and ciphertext are very sensitive, andcipher plaintext correlation is small, it has the high security confidentiality.The fourth chapter, Puts forward a chaotic dynamical system based on the pollutionencryption algorithm of the Hash function construction. In this paper, the pollution in chaoticdynamical system take the one-dimensional Logistic chaotic mapping and piecewise linearchaotic mapping structure as an example, through the analysis of experimental data andsimulation show that this algorithm and constructed pollution Hash function has good randomness and collision resistance, the algorithm can meet the various performancerequirements of all powerful Hash function.The fifth chapter, summarizes the paper and makes prospects on the research work.