Design And Implementation Of SDN Controller Platform

With the rapid development of server virtualization, storage virualization and cloud computing technology, huge change has occurred in applications hosted by network. Network architectures faced enormous challenges today. The control plane and forwarding plane in network devices tightly couple together in current network architecture, so the programmability of forwarding plane is very low. SDN architecture change the control mode of data transmission in traditional network, decouple the control and forwarding plane. All the forwarding plane in devices constitute the underlying forwarding network.This network is only responsible for packet forwarding.The control plane define different transmission path for different kind of packet, and distribute the transmission rules into forwarding devices. In the SDN architecture, openflow protocol formulates rules for connection establishment between the controller and the switch; defines the message format for communication between the controller and the switch, it is one of the most important components in the SDN architecture.This paper design and implement a SDN controller platform with openflow1.3supported. The platform could communicate with switch and supply open interface which could be used by application layer.The paper first introduce the existing works about the controller, In light of the following two shortcomings-lack of support for the latest openflow1.3protocol and the difficulties in integrating with application layer, a new framework of lightweight SDN control platform is presented.Then, the design and implementation of connection establishment module, legality verification module, callback registration module, application Interface module, device management module, message packing and unpacking module are presented. At last, an application is developed for test.According to the testing results, the SDN controller platform could initialize the connection channel with switch, the application interface is easy to use, and the most important is that it could fully support all the message exchange defined in latest openflow protocol.Finally, the conclusion is made, some problems are pointed out and the future work is proposed.