Design And Implementation Of VPN Gateway Based On IPSec

VPN (Virtual Private Network, VPN) is the extension of the intranet, which can help remote users and branch network establish security connection, and guarantee the security of the data transmission, which sovles the existing security problem during data transferring in the traditional network. Data security is guaranteed by data encryption. Compared with the traditional network, VPN establishes safe communication channel between two LANs that cannot be linked logically, and enables the data access between two LANs as convenient as they are in the same LAN.This paper aims at further research on Virtual Private Network(VPN), a popular security technique based on the IP Security Protocol architecture(IPSec). Based on the army's warehouse network, a efficient, safe and stable VPN gateway on the IPSec protocol is designed and fully tested in the paper.The following research content and achievement are included.1) The paper conducts comprehensive research of AH protocol, ESP protocol, transmitting mode and tunnel mode to IPSec to satisfy the security demands in the army's warehouse network. Based on the fact that the gateway is closely employed to the other gateway in the applicaiton, a VPN gateway based on IPSec protocol is designed, which also considers the features of IPSec protocol. This paper provides a new technique to make better use of IPSec in real application circumstance to ensure the communication security of VPN.2) The paper implements the detailed design within IKE, SAD and SPD modules in IPSec protocol. Meanwhile IPSec protocol tacticsand SA administration module of the VPN gateway were fully detailed. Additionally, GUI interface for the security strategy and management are well developed. The functions to facilitate gateway implementation are provided as well.The paper also designed an example of the security tunnel though VPN gateway under certain security strategy. Furthermore, studies were carried on the hardware-accelerated gateway and the multi-protocol application of the IPSec VPN.