Using GNS3 for constructing an emulation network environment, I give a simple topology as follows to try running NOX GUI and OpenFlow GUI.
P.S: for more information in GNS3, please refer to this:
http://www.gns3.net/gns3-virtualbox-edition/
In NOX GUI, the topology graph is created like this:
In OpenFlow GUI, the topology graph is created like this: