The End-to-end Network Traffic QoS Optimization Technology Research

In the era of rapid development of information networks, network multimedia services are emerging constantly; more and more Internet users submit comprehensive service requirements, including multimedia services communications. Traditional packet-switched data transmission networks turn towards less real-time demanding data communication(such as FTP and Email, etc.), and using TCP/IP protocol is mainly to optimize network traffic throughput and ensure the reliability of the communication. However the network is now in the state of coexistence of multiple service flows, including some strong real-time multimedia applications such as VoIP and so on. These applications include not only the text information, but also including Voice, the graph, Video, and other forms of information. This information not only requires the network transmission for higher bandwidth guarantee, at the same time needs lower transmission delay and lower jitter and lower error rate performance. Therefore, in the case of network evolving emerging businesses streaming especially some multimedia applications for real-time that the network has higher QoS demand and requires the network to provide more effective QoS control and guarantee. Thus, this article will research QoS technology optimization.This paper aims to research and optimize key QoS network technology-- Queue scheduling algorithm. The paper analyzes common queue scheduling algorithm by comparing the research and chooses WFQ scheduling algorithm of better fairness in-depth research. And this paper analyses on the basis that WFQ does not support real-time traffic flow and proposes improvements plan according to the shortcomings. And this paper brings up three kinds of improved model including BWWFQ, BPWFQ and SRWFQ. Using NS-2 network simulator to simulate improved algorithms in QoS parameters of latency, throughput and packet loss rate, the simulation analysis shows that all three models are able to make the weighted fair queuing support real-time traffic well.This idea of paper is based on first research and analysis and then suggests improvements. This paper firstly describes the background of QoS network applications. And then it researches the main network technology models in the development of QoS, which includes the best effort model, the model of integrated services, differentiated service model. This paper firstly analyzes the model principles and structure, to identify strengths and weaknesses, and then researches the main service model and the key technology. Then it researches current wider typical queue scheduling algorithm and analyzes their strengths and weaknesses. And it has in-depth study of weighted fair queuing scheduling algorithm and suggests improvements to the program. And then it uses the NS-2 network simulation software to simulate program based on improvements and improved algorithms. And then after comparative analysis of simulation results, we can know that improved program has better performance than original algorithm.