The Research For Measuring End-to-End Network Bottlenecks

With the rapid development of Internet and the explosive growth of the data communication traffic around the world, stabilization and reliability are required for network high effectively working. However, Internet performance affected by many factors, such as network architecture, processing speed of routers and switches, available bandwidth of links, the amount of users and so on. The problems of partial network nodes often bring the network performance to declining, accompanied with network delay, network congestion and other similar problems .Therefore, the study of Internet bottlenecks are of great practical significance.Bandwidth and delay are the most important parameters for the network performance, and also are the key factors for applications of network services. And they are the main content for network bottlenecks research, as the criterions of locating network bottlenecks. On basis of concepts and principles about the network measurement and its architecture, the bandwidth bottlenecks measurement theory, methods, models and related applications are discussed, especially for locating available bandwidth bottlenecks. Pathneck is a tool that can fast locate the available bandwidth bottlenecks, and it also needn't the cooperation of destination. But under the condition with bursting competing traffic and sudden delay variation, it cannot correctly locate the bottlenecks. In view of the problems that the algorithm for Pathneck locating network bottlenecks of available bandwidth, which is unable to do the effective adaptation for the network dynamically changing, we proposed a new auto-control sampling algorithm based on the length of delay distributed function, with the characteristic of Pathneck measuring the value of delay. It has some improvement in practice.Furthermore, we also have some research for the persistence of available bandwidth bottlenecks .Through the data obtained by Pathneck , we make an analysis for persistence from time and location of routers and prove the theory of bottlenecks persistence. At last, we developed a monitoring system for network bottlenecks based on the application of Pathneck.