Research And Design Of Secure Short Message Transmission

With the development of society and the progress of information technology, the mobile terminal short message communication service has become one of the most important ways of mutual exchange and communication between people, the short message service involves more and more privacy and security of users’ information, but the current communication system cannot meet the safety requirements of users.In the light of the message security issues on the transmission process as well as the characteristics of the short message service and user demands, this paper puts forward the short message security transmission system based on end to end.The encryption system uses the hybrid encryption system based on AES and ElGamal encryption algorithm to realize the encryption of SMS text and the session key. The system combine the two parts of ciphertext and the MAC authentication codes to form the SMS to be transmitted. By this way, it ensures the integrity and authenticity of the SMS text. The message between mobile terminals is encrypted by AES encryption algorithm and ensures a higher encryption speed. The session key change to be about54bytes after the encryption by ElGamal algorithm, plusing the MAC authentication code with4bytes, so the actual message encrypted content length is82bytes. If the message edited by user exceeds this length, the message will be divided into several messages, then the system will use the function of split and reorganization to make the message available as well as can be decrypted.CA achieves the confirmation of the legitimate user identity and the user public key’ signature by the certificate authority. The user deliver own public key and mobile phone number to CA for verification and signature, and CA form the digital certificate for the user. The mobile terminal gets and processes the digital certificate through the application and response, then confirm the authenticity and reliability of the sender’s identity through the CA’s public key.Finally, the mobile terminal message transmission security system mainly achieves the user SMS text encryption and decryption, message reading and sending function as well as management of keys on Android platform. The experiment shows, the short message security transmission system based on end to end proposed by this paper can effectively guarantee the transmission of SMS information security and the efficiency of information transmission as well as has a good performance.