Network View Optimization Of SDN Distributed Controller Based On Hierarchical Clustering Algorithm

Since 2008,just a few years after SDN proposed,it has achieved rapid development,the biggest feature of SDN is the decoupling of control plane and the forwarding plane,and the decoupling of control plane from the underlying network by some special means in the network.The programmable control plane begins to replace the traditional embedded control plane,the control plane will be extracted to a centralized controller,as a result,the whole network will be managed by the central controller,so that it can realize the dynamic management and flexible configure the network resource.With the development of society,the scale of the network is inevitably increasing,and a single centralized controller is prone to overload or failure.For large networks,even for a very powerful controller,it is difficult to maintain the integrity of the network because of the lack of the necessary processor and memory capacity,and will not be able to respond to network events.Once it happens,it will cause great impact on the whole network service function,severe cases may even cause network paralysis,and the single controller is also unable to cope with the problem of SDN network in a number of areas,which requires a distributed cluster,the cluster has many SDN controller,so it can avoid performance problems of single node controller.Now,in order to solve the various problems faced by a single controller,many research institutions and enterprises have put forward a new architecture based on a single centralized controller,there are two main types of mainstream architecture:One architecture is a distributed controller with a centralized database such as ONOS,another architecture is a fully distributed controller such as Onix.The above two kinds of controller can solve the performance problems of single controller,but also has their unique advantages and disadvantages.In this paper,the main streams of distributed controller are studied,and the resource overhead model is designed on the basis of the distributed controller architecture,which mainly includes the following two important expenses: the storage overhead and the communication overhead.And we put forward an algorithm to optimize the resource overhead model.The optimization algorithm in this paper is to find a balance in the two kinds of typical SDN architecture,and uses the algorithm to optimize distributed controller,the main optimization way is to improve the management of the view in controller,to reduce the total resource.In this paper,we made a large number of experiments to prove the effectiveness of the algorithm,and further explored the use of the environment,finally,this paper puts forward a lot of theoretical planning to future research directions.