Design And Implementation Of A QoS Control System For Three-layer Network Based On Service Identification And Classification

With the rapid development of network, the Internet based on TCP/IP have beenpermeated everywhere ofthe society. Large local area networks or super large local areanetworks have established in governments, enterprises, science research and educationinstitutes as well as the military departmentsone after another.Many of the networkshave the classic hierarchical structure of three layers which is calledThree-LayerNetwork for short.In Three-Layer Network, the number of users has beenconstantlyincreasing and the new applications are also constantly emerging. Therefore, optimizingthe network configuration, improving the network performance and ensuring networkquality of service have become the urgent problems to be solved in Three-layerNetwork.In this thesis, the Three-Layer Network QoS(Quality of Service) control system isdesigne and implemented based on the study of the network identification andclassification technology, combined with the characteristics of three-layer network.First of all, on the basis of analyzing characteristics of Three-Layer Network andthe QoS demand of vaious applications, aimed at the key application and non-keyapplication in three-layer network, a evaluation architecture of application prioritybased on three-layer network is proposed. This evaluation architecture can reflect thedemand of application QoS more comprehensive, and make the evaluatin the QoS moreaccurate.Next, after a general study of network application identification and classification,artificial neural network theory is used in the identification and classificationtechnology. A double-classifier is proposed based on self-organizing mapping algorithmand sample match algorithm, which is used as cooperate training. It achieves the goalsof application identification and priority classification, improving the accuracy ofidentifying the key applications.Finally, in order to applythe double-classifier based on cooperate training tothree-layer network, a control system of three-layer network is designed, implementingon-line collection, off-line analysis of network data flux, centered analysis of networkQoS status, choice of QoS control strategy, distributed sensing of network performanceand QoS demand, improving the capability of guarantee three-layer network QoS.The experimental results show that the proposed system can evaluate thethree-layer network relatively well, identify the key application accurate, satisfy thedemand of QoS of different applications and provide corresponding guaranteestrategies..