The cloud-based services has appeared to utilize virtual machines along with the popularization of the virtualization technologies evolution and the hardwares performance upgrade at a lot of date center. However it has many requirements such as extension layer2 networks, wider bandwidth of networks, insufficient VLAN IDs compared to the conventional housing services. In this paper, we describe the problems and functions which are required for the cloud-based date center. Additionally, we also introduce and explain the technologies of VXLAN, OTV, PBB, TRILL, SPB and OpenFlow to solve those problems. And last, we consider problems of interoperability which are caused by differing between vender's product strategy and users' side requirements to concern over the development of data center network.