Research On RC4 Hybrid Encryption Algorithm Integrating MD5

RC4 stream cipher algorithm and MD5 message digest algorithm are two widely used cipher algorithms,which have important applications in the fields of streaming media data transmission,network information encryption and identity security authentication.With the rapid development of the Internet,while the network provides more convenient services,privacy leakage,information theft and other issues have become more and more serious.Password algorithm attacks are frequent.The RC4 and MD5 algorithms are seriously threatened and face serious challenges.Aiming at the low randomness of RC4 algorithm key stream sequence,it is susceptible to distinguishing attacks,state guessing attacks and"behavior"attacks;MD5encryption algorithm differential path is easy to be found,security is reduced,and it is vulnerable to birthday attacks and differential attacks An RC4 hybrid encryption algorithm incorporating MD5 is proposed.This algorithm is based on the original algorithms of RC4 and MD5,and introduces random variables into the algorithm to enhance the security and randomness of the hybrid encryption algorithm.First,complete the KSA?Key Schedule Algorithm?part of the RC4algorithm,generate the keyword Key according to the current system time,and send it to the S box.After the pointer traversal operation,the initial state table S₀is generated;second,the MD5 algorithm is initialized.The generated message S₀is sent to the MD5 encryption algorithm to generate a message digest;finally,the generated message digest is sent back to the RC4 algorithm as a new initial state table S₀to implement PRGA?Pseudo Random Generation Algorithm?.The final key stream sequence used for encryption and decryption.The hybrid encryption algorithm is time-sensitive in the generation of the initial key keyword.During the operation process,the two algorithms have uncertainties.The NIST randomness test results show that the randomness of the key-stream sequence generated by the combination of the two is higher than RC4.The algorithm,theory and experiment prove that the hybrid encryption algorithm improves the security and can effectively resist the security attacks.The thesis has 21 pictures,3 tables,and 51 references.