Design And Implementation Of Solving The VPN Subnets IP Confliction

As the Internet becomes more popular, and the growth of the enterprise network application, VPN, one of the network security solutions, is widely used for remote network communication in various companies. And for the reason of the widely use of the VPN, the requirements of the users transfer from the basic security to efficiency, management, expansibility and convenience. In recent years, the secure, effective and flexible trait makes the application layer VPN solution to become one of the hottest solutions of the enterprise network security design.This paper concentrates on the solution of the data transmission when there is IP confliction in the intranet of VPN system, and the conception of the private domain name system based on it. The discussion bases on the two modules of the VPN system: the module of LAN2LAN and the module of P2LAN. The solution scheme is made after detail analysis of the difficulty of the design. The key technology includes virtual network adapter, tunnel encapsulation, routing, update checksum and dynamic domain name update. The whole system's framework is designed in detail and implemented, including central server, gateway server, remote access end and mobile end. Lastly, the test of the system is discussed. Real environment is built and simulate the actual environment as much as possible, and each aspect of the system is tested, including the serviceability and performance.Comparing with the traditional VPN, the VPN system discussed in this paper solves the problem of the communication in IP confliction between the Intranet of VPN system and the conception of the private domain name makes the user more comfortable to access the resources and makes the VPN system more flexible. Besides, it can penetrate NAT and firewall, with excellent efficiency and more stable.