Research On Quality-Of-Service Routing Algorithm In Software Defined Network Based On Heuristic Multi-Constraint Optimal Path

In recent years, with the high-speed development of the Internet, the Internet has evolved from a single data transmission network to an integrated network of data, images and voice and other multimedia information. However, the existing Internet transmission model is still the single best effort forward data service, it is unable to meet the different multimedia applications and a variety of user requirements for network transmission quality. So, to provide users with end-to-end Quality of Service is a highly dynamic research field. Traditional network architecture of providing Int Serv system and Diff Serv system are faced with many problems. For example, Int Serv system requires each router on the data path to make routing decisions, which causes the router is too heavy, high complexity; Controlling the particle size of Diff Serv system is too extensive, resulting in poor end-to-control effect. Therefore, the end-to-end controlling the particle size and lower complexity of centralized control became a contradiction, it can not be solved in traditional network architecture. But in Software Defined network architecture, the situation is the fundamental change.Unlike traditional network, control plane and data forwarding plane is separated in SDN, the control logic is concentrated in the central controller, the ordinary router only keep forwarding data logic. So to provide Qo S in SDN is an efficient method for service quality control, which is full use of the architecture characteristics of SDN. However, in the SDN, it is faced with enormous challenges that across multiple networks to achieve end Qo S routing.To solve the Qo S routing problem that is crossing multiple SDN network. This paper presents a Qo S routing algorithm based on multi-constrained parameters. Simultaneously, we propose a heuristic algorithm to select the optimal path for avoiding path congestion. And we contrast the proposed algorithm with other routing algorithm.First of all, this article introduces relevant theories of SDN, mainly includes the summary of SDN, SDN system architecture and the working mechanism of SDN. Then, this paper introduces several kinds of classic quality of service routing algorithm, including multiple constraint Qo S routing algorithm, the optimal constrained Qo S routing algorithm, the detection method of distributed routing algorithm, Lagrange Relaxation based Aggregated Cost, A * pruning algorithm, Genetic Algorithms and Ant colony algorithm.The second, according to the characteristics of SDN controller only master the network topology information of this domain and forwarder only has the function of forwarding data, and combined with the distributed routing policy and resource reserve strategy, we giveed a Qo S routing algorithm based on multiple constraint parameter.At last, we evaluate the proposed algorithm with simulation experiments based on the scene of SDN, and give the appropriate algorithm analysis. using test data to verify and compare. And compared to the other two Qo S routing algorithms, the Qo S routing algorithms that is proposed by us can significantly reduce Qo S request packet, While the number of reasonable number of paths is smaller than the number of paths by using flooding method.