Research And Implementation Of Traffic Scheduling Technology Based On SDN

In recent years,video surveillance and video live streaming are springing up,with the popularization of multimedia technology.One common feature was found from These multimedia applications,that is,multiple clients visit a same resource site at the same time,which is very similar to multicast structure.While Sichuan Telecom wants to transform its original video monitoring system,we took this opportunity to improve the system architecture of traditional video surveillance,live video,etc.,with multicast technology as the core,and service chain scheduling technology and traffic push technology as auxiliary.A software-defined networking(SDN)-based video surveillance system was designed.At present,the implementation of the traditional network multicast scheme has many problems: first of all,the application system and the network is not closely linked,so it can not adjust the network traffic scheduling strategy according to the specific application of the real-time network situation,so that imbalance occurs;secondly,flow scheduling strategy of traditional network architecture is lack of flexibility,leading to the poor stability of multicast application;finally,the traditional multicast architecture lacks a real-time alarm system,and cannot find the multicast source fault or link failure.In addition,multicast routing algorithm has two problems: first,do not have the ability of routing with multiple QoS constraints,or most of the algorithms is focused on one or two constraint conditions,and can not accurately reflect the status of the network;second,the algorithm only care about how to route the traffic,leaving the consequences of fragmentation of bandwidth resources alone.In this thesis,traffic scheduling is studied in the SDN environment,and the multicast technology and service chain technology are used as the breakthrough point to improve the traditional multicast architecture.The main research work of this thesis has three points: first,improve the ant colony algorithm,and add the preprocessing and load factors on the basis of ant colony algorithm,which can speed up the algorithm convergence.The construction and maintenance of the multicast tree using this algorithm to multiple QoS constrained multicast routing,and reduce bandwidth fragmentation as much as possible;second,we improved the SDN service chain,puting forward the concept of one-way and two-way service chain service chain,and to achieve a one-way service flow scheduling scheme in the chain.Third,based on the above two points,the multimedia multicast architecture baseed on SDN is designed and implemented.SDN based multimedia multicast architecture has the following advantages:(1)strengthen the connection between the application layer and the underlying network;It can be used to measure network conditions in real time and to provide data support for multicast traffic routing.(2)the improved ant colony algorithm can be multicast routing under the QoS constraint of four dimensions,and can reduce and utilize the bandwidth fragmentation as much as possible.(3)the flexibility of flow control based on SDN makes the function of the service chain be realized,and the user can customize the multimedia monitoring system by themselves.A typical application is the real-time alarm function.(4)the road failure recovery can monitor the link failure at any time and adjust the traffic scheduling strategy in time,so that the ability of link failure tolerance can be improved.