Abstract: In order to improve the transmission security of electronic files and the security of user information,a chaotic sequence based encryption method for uploading electronic files is studied.The formal scheme is used to decompose the steps of uploading electronic files,and the form of uploading is defined uniformly in the interactive process.Logistic mapping is used to represent chaotic mode.Given the interval of chaotic sequence,the file encryption key stream is randomly generated.On the premise of ensuring the complete decryption of electronic files,the replacement process is constructed by setting ciphertext replacement rules,adjusting ciphertext order according to reversible relationship,realizing the encryption and uploading of electronic files,and completing the method design.The experiment simulates the whole process of uploading electronic files based on the configuration of optical fiber network.The chaotic sequence method can generate 128 bit encryption key within 10 s and complete 498 groups of electronic files with memory size of 1.5 GB within a specified time.

Key words: ciphertext replacement, electronic records, chaotic sequence, logistic mapping