No Parking Fee System Network Information Encryption Technology Research And Implementation

A lots of Sensitive information from Speedway No Stop Electronic Toll Collection System have to be transfered through net work , the security of sensitive information determine security and stability of the system. Information encryption is very important process to protect information security, and it is also the core technique to realize network information security.Cryptograph system divides into the public key cryptograph system and the symmetrical key cryptograph system. The symmetrical key cryptograph system have the single key to implement encryption and decryption fast . The public key cryptograph system have tow keys ,one is the public key ,the other is the private key ,and its encryption process is different with its decryption process. The public key cryptograph system have lots of excellence ,but its speed to encrypt and decrypt is very slow,and it can't suit for practical needs if we encrypt all message to transfer through network.Circle function of algorithm have many advantages, simple implementation, fast encryption and fast decryption, good resistance to be attacked and so on, so AES is a more ideal symmetrical key algorithm. RSA has been proved a safe public key cryptograph algorithm for many years.The system use a encryption technique conjoinning AES algorithm and RSA algorithm for eliminating safe hidden trouble, which arise from network transfer of conversational secret key of the symmetrical key cryptograph algorithm. Circle function of AES algorithm composed of substitution and confusion manage all group data side by side (It comprises four transformation. The first is SubBytes, which use S-box to implement groping byte substitution. The second is ShiftRows, which is a linear combinatorial permutation. The third is MixColumns, which is an arithmetical substitution in field 2~8. The fourth is AddRoundKey, that is to say circle secret keys carry out similarity and or operation with superstratum result). RSA algorithm is designed according to the difficulty to decompose big integer. It implement information's encryption with unilateral trap door function(if M is plaintext, and if C is...