Research On Quality Of Service Technology Base On Software Definition Network

With the rapid development of modern network technologies,more and more types of services have been separated from the network,and the number has rapidly increased.At the same time,the customer's demand for services is also increasing.This has led to the gradual weakening of the network's management and control capabilities,and the increasing number of problems in the network,creating difficulties in guaranteeing the quality of service(QoS)of various services.Therefore,improving the current network architecture and proposing a new architecture suitable for network development has become an important topic at present.SDN(Software Defined Network)is a new network architecture born on Stanford University campus network.The core idea is to separate the network control plane from the forwarding plane.Based on this architecture,this paper improves the ant colony algorithm and designs and implements a new routing system.This system can select the best link for the service flow,thus ensuring that the corresponding service can be assigned to the most suitable chain.On the road.This paper proposes an Ant Colony Optimization of Resource Guide(RGACO),which uses RGACO as the routing algorithm to calculate the path for the data flow.The obtained path can meet the requirements of certain delay and packet loss rate.First of all,this thesis introduces the research background and basic concepts of SDN.Then it introduces OpenFlow technology including Open Flow switch and OpenFlow protocol and OpendayLight controller.Then,this paper presents the RGACO algorithm.Since the traditional ant colony algorithm does not take into account the QoS requirements such as bandwidth and delay,this paper has made four improvements on the basis of it: according to the corresponding requirements of the service,remove the links that do not meet the requirements from the network topology to establish new ones.The network topology;modify the condition of the pathfinding;modify the path objective function;and improve the pheromone update method.Then,this paper designs a new routing system.The main functional modules of this system are global topology module,ant colony routing module and resource statistics module.The resource statistics module periodically measures the link bandwidth,delay,and packet loss rate,and collects and uses these network conditions to calculate and use the link.The ant colony routing module collects the information from the network resource statistics module.According to the RGACO algorithm,the route that meets the QoS requirements is calculated for the service.The global topology module mainly learns the global topology.When the controller captures the event that the node and the link state change trigger,it will call the corresponding method to handle the event.This module The corresponding event processing method defined in the main work is to record the global topology information,to facilitate the use of other modules.In this paper,the secondary development of the Opendaylight controller and the simulation network with OVS as the switch are tested and verified.