Analysis And Improvement Of Data Encryption Algorithms

With the rapid development of the Internet,the information security has becomemore and more important and the data encryption algorithm is a good way to protect thesecret information.In this paper some data encryption algorithms are analyzed andimproved.In Chapter2the basic knowledge of the encryption system is introduced includingsymmetric and asymmetric encryption algorithms,hash functions,digital signatures.Weanalyze the DES algorithm and give the procedure that how the plaintext is encrypted tociphertext.In addition the double and triple DES are studied.Some public key algorithmsare learned just like RSA,ElGamal,ECC.And they are compared in security andefficiency.In Chapter3the Merkle-Hellman knapsack public key algorithm is analyzedalthough it has been broken by many other algorithms.We have proposed an algorithmbased on another easy solvable problem and the improved algorithm can resist Shamir’sattack and the low density attack.In Chapter4the RSA algorithm has been improvedusing the Chinese Remainder Theorem.The decryption speed and the security are allraised.With the improved RSA,we construct a cryptosystem which contains manytechnologies just like certifications,protect the public key,digital siganatures.In Chapter5the chaos system has been introduced and we have a chaotic encryption experimentfor pictures,which gives an exciting answer.At last we give a conculsion and talk aboutthe future work.