Mixed Encryption Algorithm Research Based On IPSec VPN Data Security

With wide application of Internet network, the network information security becomes more and more important. There are more and more research and application on technology concerning the confidentiality of communications between computers. By using the public communication facilities, such as Internet, VPN (Virtual Private Network) establishes a secure, virtual and dedicated channel through the tunnel and encryption technology so as to ensure the confidentiality of data within the local area network. VPN technology can not only provide corporate users with data transmission security, but also cost savings. IPSec VPN is the protocol suite used most widely among VPN architecture, but its mandatory requirements of the encryption algorithm can not meet people's needs. we put forward to a new algorithm in my paper. The algorithm is the combination between the High encryption algorithm (AES) in the symmetric algorithms and the elliptic curve encryption algorithm (ECC) in the asymmetric algorithms. The AES algorithm selected by NIST is simple, efficient and safe and has a good algebraic structure, and the ECC algorithm is faster with short key and has less resource when realized.In my paper,I introduce the concept and structure of IPSec VPN firstly,then outline the basic theory and development of the crytology. I separately analysis AES and ECC algorithms' encryption processes and their safty. Finally I propose a mixed encryption algorithm and research on the mixed encryption mechanism by desgning simulately IPSec security protocol.The simulation system, based on IPSec VPN data transmission and mixed encryption algorithm, is realized by the C++ language and standard Windows Winsock API and is divided into server and client. It fully shows the performance and data size of the mixed encryption system and the relationship between number of ports at client and data transfer rate. Based on the test data, this paper analyzes the security and anti-offensive of the mixed encryption algorithm.This mixed encryption algorithm with integration of the two algorithms has a higher level of security and implementation and thus can effectively improve the VPN data security and data transfer rate.