Abstract-The demands for the next generation internet testbeds are becoming more and more intense recently. However, there are three problems need to solve, i.e., the ever-increasing number of actual or virtual machines demands, effectively manage these different machines and maintain the effectiveness. A scalable layer 2 network that across the whole internet is a very important technology to solve them. This paper proposes a new software defined network (SDN) based scalable layer 2 network framework and its significant characteristic is to build a scalable layer 2 network that across the whole internet by using SDN's technologies. Our framework has high performances because: 1) The operation of encapsulating and unpacking packets is not necessary; 2) Routing paths can be pre-computed; 3) Traffic engineering to be implemented. And then the proposed framework has good scalability because its addressing resolution can be done either by a centralized query or by transmitting a broadcast packet in the internet. And the two ways can be swapped flexibly by the load balancing.