Research On The Technologies Of Admission Control In Network Congestion Control

Congestion control is an important technology that supports normal executing operation in the entire network system architecture. It was implemented through the collaboration mechanism from the source node to the destination node and the router in transmission path. In particular, the current rapid growth of Web services and the servers are deployed in large numbers in the enterprise-class access networks turned this position to the bottleneck of network transmission. So how to implement of the network access layer congestion control effectively, make sure the enterprises network service traffic quality of service and improve network resource utilization is the main research content of this thesis.The two types of congestion control mechanisms: system deployed in the terminal and gateway were reasearched in this thesis.The related technologies of network congestion control in the admission control and the Web services to access networks of traffic characteristics were analyzed. How to monitor of business traffic through the gateway in real-time, forecasted the network congestion timely by detected the state of network transmission and control the network traffic through admission control were researched. The main works done in this thesis are as the following:①The status of network congestion and factors causing network congestion were analysised in the thesis. The current network congestion control mechanism: end system congestion control and gateway congestion control mechanism were researched in the thesis. The relevant technology in admission control is investigated. A theoretical foundation was provided for admission control algorithm application in network congestion for this thesis.②Network flow characteristics of enterprise-class network were analysised in the thesis. Servers are deployed in large numbers and provide Web service to Internet int the enterprise-class network. A model of adaptive admission control for the access layer position and application deployment scenarios was proposed to congestion control and improves the business flow quality of service.③A dynamic strategy of adjustment the measurement time window measurement was proposed which overcame the problem of traditional fixed time window of measurement parameter to ensure network quality and improve utilization of network resources. Meanwhile, an accepted criterion for high-bandwidth flow algorithm for admission control was proposed. This algorithm monitoring and measuring the high rate of congestion-sensitive real-time flow, using transformation detection formula, discovering network congestion timely and accurately, in order to control network congestion, improve service quality, increase utilization of the network resources.④An admission control prototype system was implemented under Linux netfilter framework. The experiment test proved that the system model is correct and effective.