Research Of Load Balance And Traffic Engineering Based On SDN

Nowadays, with the constant development of the computer network technology, the network protocols and structures become more complex and hard to maintain. Stream media, video conferencing and cloud computing services, the widely application of new network applications, makes the quality of service demand is higher and higher, how to improve the IT infrastructure and guarantee quality of service for these new services now is becoming a top priority. People find it difficult to solve the problem based on the existed network protocols and structures. In recent years, SDN, a revolution of a new network structure, provides a creative solution for the network. SDN can fundamentally solve some existed problems, and meet the demand of today’s network progress.SDN network allows developer to control network flow by using the method of network programming. Through the SDN controller, users can monitor the network resource state of the equipment timely and globally. When the network state changes in the underlying network, the equipment will send notification to the controller, the control opportunities according to the internal algorithm to calculate the optimal result, then feedback to the underlying network equipment. The underlying equipment will schedule the network data according to the calculated flow information. SDN conduct the next generation network platform, enhance the response speed of the network, and increase the forward speed of point to point.OpenFlow is a novel separation of forwarding and control structure. The OpenFlow controller provides management of the network, the OpenFlow switch take charge forwarding by matching the flow table. In this paper, we outline the origins and development of SDN, illustrate the OpenFlow protocol, as well as the details of the Floodlight controller and Open vSwitch technologies. The main work of the paper is as follow:Firstly, in the network structure of SDN, we present an analysis of variance load balancing based on SDN network. The traditional load balancing cannot realize dynamic adjustment of the whole network, and the capability of sensing changes in the network environment is poor. This paper presents a new method of using analysis of variance to monitor the web server port traffic and reorienting network traffic by using probability algorithm. When a user access request arrives at one equipment, SDN controller will dynamically dispatch the user request to suitable server based on the network status, realize the load balancing. When severs load is imbalance, the controller will analysis the data flow and find the most data circulation path. By replacing this path with other server path, the controller dynamically adjust the flow of data flow. This method can provide comprehensive fault tolerance from access, forwarding to service and bring the total load of server cluster into full play. Experiments show that this method can effectively solve insufficient of the existing traditional load balancing reliability and the shortcoming of uneven load.Secondly, in the network structure of SDN, this paper designs and realizes classification model of traffic engineering. Traditional routing protocol routes and forwards message according to the shortest path routing, when the short circuit is full, the new flow still imports the network without shunting processing. To solve this problem, this paper present a hierarchical model based on traffic priority. The controller will shut processing flow based on business priorities when the shortest path in network is congestion. The architecture and realization of the function are introduced in detail. Finally, Then, we design constructing SDN network topology to test our arithmetic and model function, and analyses the test results, verifies the load balancing arithmetic and traffic engineering model in the SDN network.Finally, we propose the next direction of research about this paper.