Multi-protocol Label Exchange Of Vpn Encryption And Encapsulation Technology

In the tranditional scheme of enterprise network.no other better method except hiring DON or FR can connect remote LAN to LAN. Motive users or remote users can access independent enterprise LAN only by dialing. With global development and motive users increasing, relation among customers become more complicated. This scheme must result in expensive long-distance call charge. And then , the concept and market of Virtual Private Network emerge.This paper is mainly on the subject how to consider efficiency and security of transport as a whole,and presents a VPN scheme including the advantages of IPSEC and MPLS. Because tunnel technology is adopted , VPN can guarantees private data to transport safely on public networks.It makes enterprise reduce the expense of communication, installing and maintenance, simultaneity makes enterprise implement function of extending conveniently, constructing networks with partners and controlling entirely. There is some problem such as no QoS guarantee and no CoS implement on VPN. CISCO put forward a thougt to implement VPN with MPLS technic on March, 1999. Due to only once route when a package pass by MPLS network , it heightens efficiency of network greatly. Besides, it can provide enormous service control and traffic engineering mechanism, so MPLS makes the network more quick and more controllable. But this method has the shortcoming of information leaking. Based on MPLS, this paper presents the thought and implementing technology that encrypt the data by IPSEC at the Customer Edge (CE) router and encapsulate the data at Provider Edge (PE) router. The problem of information leaking due to at MPLS backbone has been resolved.Considering regional characteristic and involved equipments, MPLS VPN is a huge system actually. This paper focuses on its mechanism , implementing process of encrypting data at the Customer Edge (CE) router and encapsulating at Provider Edge (PE) router. Some particulars are implemented with C++ Builder 5.0: creating and sending of IP package, encrypting of IP packet, encapsulating of encrypted IP packet, sending encapsulated IP packet to MPLS backbone. The result from analyzing and comparing the performance of different VPNs is satisfiable.