One of our ongoing works with 3N is developing a small network prototype, as shown in Figure 3. In this prototype network, the control network mainly consists of two controllers, and the management network mainly consists of two managers, and the forwarding network consists of two forwarders, two separators and two end systems. Also the forwarders and separators are parts of the control network, and the separators and Control1er1 are parts of the management network.