Due to the existing IP MAN designed only to meet the deployment of basic business requirements, for the lack of QoS, MPLS VPN, network security, and other aspects of the strategy deployment,it cannot discriminate between the different business and cannot satisfy voice and video business bearing quality. At present,from the business development of the telecom operators, the big Customers’VPN service only have a small amount of development in some cities.Because of MPLS VPN with low cost, safe, reliable, easy maintenance and other advantages, Compared with the traditional private line services, users are increasingly like MPLS VPN services. For voice and video services, how to provide customer satisfaction service has become the focus of attention.This article will study for the QoS solution of MPLS VPN.This paper firstly introduces the concept and working principle of MPLS VPN, and put forward two solutions of MPLS VPN’s QoS against the characteristics of MPLS VPN and existing problems of the QoS. The first kind is DiffServ combined with MPLS, this paper analyzes the system model, its main component and the working process of the DiffServ over MPLS model, and introduces the DiffServ model in the application of MPLS VPN. The second way is DS-TE, which combined with the characteristics of DiffServ and traffic engineering and effectively avoided the packet loss and waste of network resources due to the uneven distribution of traffic. DS-TE solved the scalability and effective routing policy, it has the ability of supporting a variety of types of business. In the network model of MPLS VPN, it often appears that many VPN users share the LSP between PE-PE which will lead to resources of preemption. This paper puts forward a solution to solve this problem based on the ideal of dynamic bandwidth allocation algorithm. The traditional method is that everyone has a fixed bandwidth, The new method uses dynamic allocation of bandwidth, VPN users can be agreed with the operators of a minimum guaranteed bandwidth according their own traffic,when there is a sudden flow or users require more resources, it will allow users to expand their bandwidth according to the currently idle resources in the network.For the VPN service,We have improved the original bandwidth allocation algorithm.The original algorithm is to allocate bandwidth resources based on the weight of each VPN, which makes the low weight user have little access to the spare bandwidth. Improved algorithm solved the problem, because it allocated the spare bandwidth for each user based on the real-time traffic.We use the OPNET network simulation tool to simulate the two solutions which we studied in the paper.It can be seen form the comparison results,whether it is in the network under light load or network congestion, the DS-TE is better than DiffServ.Simulation of improved programs and traditional programs can be seen that the improved program can significantly reduces the user’s loss when the user has burst traffic,and flow which is in excess of the minimum guaranteed bandwidth also has QoS guarantee. |