The rapid development of computer technology will be the whole world as a whole, the widespread application of instant messaging technology to bring great convenience to people's lives, while privacy protection has become a more significant problem. For ordinary it's hard to equip themselves with a cryptograph machine. In this paper, through in-depth study of elliptic curve cryptosystem ECC and advanced encryption standard AES encryption algorithm, according to the characteristics of public key cryptography, elliptic curve version through the establishment of Diffie-Hellman key exchange protocol, combined with AES, design a set of perfect forward secrecy mixed cryptograph system .The system can guarantee the security of communication, easy to implement, the operation speed is quick and the cost is low. At last, the security of the system is analyzed under the environment of common network attacks.Keywords-ECC Hybrid-system Privacy-protection Forward-secrecy Key-Management
I. INTRODUCTIONWith the rapid development of information technology and Internet technology, communication technology service system and application booming, brings great convenience to people's lives, but also brought new challenges, the security problem in network communication has attracted more and more attention. At present, how can the communication security in the open network environment be guaranteed in network communication?. With the advent of the information age, information security technology has also become increasingly important. Data security and complete implementation of online transmission are the research purposes of information security technology. Among them, data encryption technology is the core of information security technology. Data encryption as a data security technology has a long history, dating back to ancient times, such as the 2000 BC, the ancient Egyptians will use some methods to protect their written information.