The Research Of SDN-based Traffic Engineering In Data Center Network

Data center has been the core of information infrastructure during the rapid development of cloud computing.New services lead to rapid growth of internal traffic within data center and a large amount of traffic interact between servers and virtual machines,unlike traditional internet traffic.Traditional network technology dosen't match the explosive growth of data center in scale,uneven distribution of resources leading to link congestion and enlargement of end to end delay seriously restrict the improvement of data center's performance and quality of service,a new network management technology must be enforced.SDN-based data center network has incomparable advantages compared with traditional data center network.Based on the global network view and real-time performance and status of network resources,SDN controller make a better routing decision for data traffic in order to achieve a optimum load balancing effect.The main work of this paper illustrates from the following five aspects:(1)Outline of the research background and the significance of data center network.A summary of the application of SDN in a variety of network scenarios was made,focusing on the application of SDN in data center network traffic engineering.(2)Illustration of the definition and the architecture of SDN,including OpenFlow protocol,OpenFlow controller,OpenFlow switch and the secure channel between the controller and the switch.A comparison among different OpenFlow versions was made,and the development process of Ryu controller used in this paper was emphatically introduced.(3)A mathematical model of optimization for ECMP based on data center fat-tree network was established,and then an end-to-end link utilization based simulated annealing algorithm was presented to calculate the distribution proportion of traffic among ECMPs.(4)Introduction of the overall idea of the Ryu controller in this paper and description of a sub-module implementation principle,including LLDP-based topology discovery module,link state acquisition module,flow table distribution module and topology view module.(5)The data center network was simulated by Mininet,and the SA-ECMP algorithm presented in this paper was confirmed.The SA-ECMP algorithm has a good effect in improving bandwidth utilization of network and reducing end to end delay.