Joint Control And Management For Multi-Area Network

SDN (Software Defined network, SDN), an emerging network architecture which separates network into a control plane and a forwarding plane. These two planes constitute an open programmable network architecture system. The control plane uses Southbound Interface of OpenFlow to get the topology and status information of the network to formulate the relevant routing strategy for the management of the forwarding plane, and abstract the underlying network for the upper application data acquisition.Due to the bottleneck of controllers, the scale of a single SDN network can not be large. According to the data, SDN controllers can support up to 1000 switches and 250000 hosts, so we need a much more scalable network architecture which is called the level of interaction between controllers. The architecture separate the SDN network into many subnets which in this thesis is called SDN areas, and each region’s controller completes regional routing through the basic interaction. In order to ensure the data synchronization and sharing of controllers running in the distributed computing nodes, this thesis adopts the distributed coordination module ZooKeeper to synchronize state information and ensure the consistency of the regional path, realizing regional routing.Using the shortest path based on the hops to complete the regional routing has obvious problems. It is difficult to meet the complicated flow characteristic, which maybe causes an unbalanced utilization rate of the partial network’s resource and affects the quality of the service. Traffic matrix estimation can achieve the network load balance and the optimization of the routing algorithm, so there are a variety of implementations about traffic matrix estimation in the industry. This thesis compares the advantages and disadvantages of the indirect measurement and the direct measurement about the traffic matrix in a SDN network, combines with some implementation about the direct measurement way in industry to put forward a heuristic algorithm, and completes traffic matrix measurement accurately.This thesis finally makes all controllers maintain global topology at the same time, and combines the traffic matrix and the bandwidth of virtual connection in the area of measurement, virtualization more fine-grained virtual global topology, completed about shortest path calculation by the source side controller, finally with the help of other controllers complete the regional routing and issue the corresponding flow entries.This thesis first describes related technologies of the level architecture of controllers, the second chapter combines the ZooKeeper to realize basic regional routing, the third chapter introduces several ways of the traffic matrix measurement, the fourth chapter achieves regional routing with incomplete information, the fifth chapter sets up the simulation platform, completing the measurement and the comparison of relevant data, finally, the paper summarizes the research and plans the next step of work directions.