Abstract: Requirements such as virtualization, automation, flexibility and scalability are given out by cloud data center network. SDN technology meets these requirements well with its features of separation of control and forwarding,centralization control, capability of open network, etc. SDN is widely adopted in cloud data center network recently.Resources such as virtual machines, bare -metal servers and dockers are provided in cloud data center. In order to manage the whole network for all these resources, SDN can be classified into three categories including hardware scheme, software scheme and hybrid scheme. This paper gives out research and analysis on three schemes and then makes suggestions on how to use SDN in the real cloud data center network.

Key words: data center, cloud computing, networking, SDN