The Research And Application Of MPLS Based VPN And QoS

MPLS (Multiprotocol Label Switch) is a core technology for next generation networks. It combines the flexibility of IP hop-by-hop routing with the quality of connection-oriented ATM protocol. MPLS VPN is a technology of IP-VPN based on MPLS, by using MPLS on the router and the switcher, simplifying the routing way of core router and combining the technology of label switching with the technology of traditional routing. MPLS VPN can be used to built the wide-bandwidth intranet and extranet to meet the demands of many kinds of flexible services. It can make the different service systems run over different VPNs and can promise the dffective isolation of different services and the service quality of effective services. It can provide the converging ability of the data, the audio and the video, and can connect seamlessly with IP service data stream on upper, such as Web, VoIP, H.323.MPLS is the basic technology which is considered well solving the QoS problem of IP backbone network. It can provide connection-oriented service by the way of connectionless or showing route by combining the link-layer switching with the network-layer routing, for reducing the complexity of forwarding, that make it to be suitable for the dynamic tunnel technologies and to guarantee the the QoS demand of data transmission service. There are three ways to realize QoS in MPLS: DiffServ, Constraint-Based Routing Label Distribution Protocol (CR-LDP) and the expansion Resource Reservation Protocol (RSVP). There are two models to describe QoS in MPLS VPN——Pipe Model and Hose Model.There are more and more demands of building enterprises Virtual Private Network and converging of the data, the audio and the video. Considering the MPLS Network actuality of Chongqing Telecom and the problem of building enterprises'VPN based on the MPLS Network of Chongqing Telecom, such as the service expense of PE equipment, the limit of interface number and type, the performance pressure, this paper discusses the key technologies of MPLS VPN and QoS, proposes a network design scheme of enterprise VPN based on the MPLS Network of Chongqing Telecom, which is an enterprise VPN example of Chongqing Telecom. At the same time, because the data running over the enterprise VPN include the multimedia data, such as the audio and the video, their demands to bandwidth, delay, real-time are different. The network must differentiate different communication and provide corresponding services for supporting...