Design And Implementation Of Cloud Middleware Based Vpn System

Internet applications have been undividable to people in daily life. As continuous privacy leak incidents happened in recent years, people’s concern to the security problem of web service has been much more serious than ever. VPN technology has been widely applied as an edge tool on web security. SSL VPN applications have fixed some drawbacks of original IPSec VPN. SSL VPN has become a more convenience and more secure VPN solution, especially on web service applications. It is an important issue to modify present VPN system.Original VPN systems mostly run on a single server machine or a single gateway device. The load capacity, expandability and stability of such VPN systems will face great challenge in front of future requirement. Although many VPN products are already strong enough, their space for improving is seriously limited. This thesis focuses on how to make the VPN system break the above limit.Firstly, we introduce the basic conception and theory of VPN, along with some classification and comparison and detailed introduction to SSL VPN. Then we introduce the background of cloud middleware and describe some load balance policies. After that, we compose a way to improve the load capacity, expandability and stability of VPN system, in which the VPN system runs on a cloud middleware based platform. In this way, the characteristics of cloud computing are combined into the VPN system. Based on software engineering theory, we make sufficient earlier analysis about requirement and feasibility. Then we design the VPN system from a whole to specific modules according to the earlier analysis result. Finally we implement the desired VPN system. In order to improve the resource utilization and stability, we also design and implement a double layer load balance policy. At the end of this thesis, we test the system and conclude the advantages and disadvantages. Besides, we propose some feasible improving directions.