Research On Data Center Network Based On SDN/OpenFlow

Cloud computing technology is developing quickly, mobile Internet is also developing at the high speed. Many new technologies,such as the Internet of things and big data applications,are being used by more and more people and the bandwidth of the access network increases quickly.The high-speed development of these computer network technology lead to the sharp increasement of the data flows in data center network.A Internet data center has hundreds of thousands of physical servers and millions of viutual machines.In order to connect these servers,we need thousands of switchboards.If we construct the network using IP network framework,that will bring to many problems,such as complex network structure、network equipment is difficult to manage and maintain、extremely difficult to locate and remove the fault、new service is difficult to be placed on current network.In order to deal with these questions and meet the ever increasing flow demand in data center,A new type of network architecture, Software Defined Network(SDN),is proposed and be extensive used in the network. Software Defined Networking is a new networking paradigm that separates the control and forwarding planes in a network. This functional separation and the implementation of control plane functions on separate centralized platforms have been of much research interest due to various expected operational benefits.Meanwhile,SDN provide developers with open application programming interface.Users can develop and deploy their own business in the network according to their needs.Now,OpenFlow is a concrete realization of SDN,that is a mainstream interface between the control and forwarding planes in a network,is widely used in the industry.In this thesis, we will research management function of two layer network in data center networks, meanwhile achieve spanning tree protocol in topology-based hybrid SDN and provide a few special flows with Quality of Service.I use open source POX as the controller and develop a few applications to achieve common-sense functions in two layer network.But OpenFlow protocol cannot meet some special demands,so I change OpenFlow protocol to adapt to two layer network, such as VLAN(Virtual Local Area Network) configuration,queue management,mirror management.In the actual network,SDN switchboards cannot replace ordinary switchboards,so we need meet the topology-based hybrid network.In this situation,the controller cannot get the whole topology of the network,so I achieve spanning tree protocol in the topology-based hybrid network.In the network,some important flow need be provied Quality of Service,so I design a approximate algorithm to deal with the shortest path problem with restricted conditions and find an approximate shortest path and meet all restricted conditions and provide Quality of Service guarantee.