Diffserv Over Mpls Model-based Flow Control

Quality of Service provides a reliable guarantee for the application of multimedia, and becomes a hot spot in the research of networks recently. Two models about Differentiated Service and Multi-protocol Label Switching supply an available route to resolve the question of IPQoS, the technique of traffic control based on Diffserv over MPLS is studied in this paper.Firstly, the development of IP QoS architecture is briefly discussed, and three kinds of architectures: Intserv, Diffserv and MPLS are demonstrated respectively, then the difference of them is compared in expandability, robustness and QoS. In order to improve IP QoS, the architecture of Diffserv over MPLS is researched on the basis of three models, in addition, framework and implementation about it are discussed, and in contrast to the others, the advantages of Diffserv over MPLS are analyzed.Secondly, after deeply analyzing current algorithms, the paper concentrates on technique of traffic control which includes queue management and scheduling, a dynamic queue management algorithm is proposed to enhance their expansibility and robustness, and the DRR scheduling algorithm is also improved. Comparing with other existing algorithms, their benefit in latency, jitter and fairness are presented. Then, the simulating experiments about dynamic queue management algorithm and improved DRR algorithm are performed, the results indicate that the improved algorithms are more robust and able to make more use of network resource.Finally, a summary of the QoS is discussed, and expectation is devised in some aspects about future tasks, although many schemes have been put forward to resolve QoS presently, the technique of traffic control based on Diffserv over MPLS is still in experimental phase, expansibility and robustness about it ought to improve frequently.