Research On Multi-path Routing In Software-defined Network

With the development of the Internet,people's dependence on the network has gradually increased,thus more and more complex types of services and surge in traffic in existing networks.Due to the different needs of users for the traffic,various types of network services have also emerged.The traditional network structure can not meet the increasing demand for network services.In order to effectively manage the network and meet the increasing demand for network services,network researchers proposed Software Defined Networking(SDN).In SDN,the control plane is separated from the forwarding plane,and a standard southbound interface protocol such as Open Flow is used in the forwarding plane to provide a standard communication interface to the control plane.The network administrator can program and control the entire network at the control plane.SDN also provides an API that simplifies the implementation of common network services,and it has been widely used.However,for existing routing strategies,their parameters are too fixed and the path selection result is relatively single,the possible result is local link congestion.The overall network resource utilization efficiency is low,and the user's communication needs cannot be satisfied.Under such a background,this thesis analyzes the problems existing in the multi-path routing SDN and proposes a multi-path routing strategy based on service demand classification.The main contributions of this thesis focus on the following aspects:1.The current status are described in detail,which include the relevant research on SDN multi-path routing at home and abroad,and the shortcomings of the traditional multi-path routing strategy are analyzed.And this thesis introduces the concept and architecture of software defined network,and this thesis also introduces the core technology of Open Flow in software defined network.2.In order to improve the utilization of network resources and solve the problem of network traffic congestion,a multi-path routing strategy based on service demand classification is proposed on the basic of the full use of network resources and user demand for different services flow of real-time and security requirement differences.It mainly includes three modules as follows: the initial path building module,the path selection module based on the network state and forwarding module based on the data flow classification.The scheme not only can meet the constraints such as Qo S demand and link capacity of user transmission process,but also can ensure the real-time and security needs of data flow.3.This thesis uses experimental analysis and theoretical analysis to verify the effectiveness of the proposed scheme.The experiments include the design and the implementation of the proposed scheme.Through the related experiments,the effectiveness of the proposed scheme is verified by comparing the time delay with the shortest path priority algorithm.In theory,because of the advantages of this scheme compared with the traditional multi-path routing strategy,it shows that the scheme can ensure the user's security requirements and improve the network load and improve the Qo S.This thesis proposes a multi-path routing strategy based on service requirements.In the SDN network architecture,the controller of the control plane centralizes the management of the entire network topology state and holds the global view of the network.In the communication process,in order to achieve load balancing and improve security,the SDN controller obtains the global network topology information,and monitors the network status in real time,calculates the path performance,evaluates the path cost,and selects an appropriate communication path.