The QoS Research Of VPN Based On MPLS

Virtual Private Network(VPN)is in fact a provisional, safe connection which is created on a public network(usually Internet).It is a safe and stable tunnel by which the messages can traverse through the disordered public network.Generally, VPN is an extension to the intranet;it can help the distance consumers,company branches,commerce buddys and suppliers to build credible and safe connection with the intranet of the company,and should guarantee users' data transmited safely.MPLS(Muti-Protocol Label Switching)is a kind of technology which is able to provide switching for various businesses.It has resolved the limitation existing in packet switching of the traditional IP.Additionally,MPLS can provide VPN business,and it is also the technology which can provide control and management related to the multilayer network integration.VPN that is based on MPLS has many advantages,but it still has some problems about QoS and safety.This paper studies and discusses the QoS and safety of VPN based on MPLS.The paper firstly studies the basic principle of MPLS,the relevant protocols,the QoS service system and the system structure of VPN based on MPLS.Then,based on those foundations of studies,it proposes a model that can resolve QoS problems of VPN.The model integrates MPLS and Diff-Serv into a bady. It can provide better QoS of pear-to-pear for the consumers. And Diff-serv is realized in MPLS network,which has obvious superiority relative to tradition IP network.MPLS introduces connection-oriented mechanism for IP network,creates label switching pathes to transmit packets,and can definitely instruct the route from the source to the destination.Those make Diff-serv in MPLS be able to resolve the QoS problems caused by traditional connectionless IP.During the process of concrete realization,in order to build LSP to support Diff-Serv,LDP(Label Distribution Protocol)is extended.