The Global Environment for Network Innovations (GENI) is a NSF sponsored effort to create a large scale testbed for network experimentation. One feature of GENI is its use of OpenFlow (OF), a specification implemented by switches or routers that allows the forwarding plane to be modified by a controller in software. Recently, GENI has made strides towards enabling experimentation over wireless resources. It is a priority for GENI to provide mobile hosts with seamless vertical handovers using IPv4-compatible methods within GENI's heterogeneous wireless networks. This feature is desirable to researchers testing network applications as well as vertical handover decision algorithms.

Our contribution to this effort is the design of an OF-based, IPv4-compatible vertical handover testbed for use with GENI wireless networks. In the spirit of GENI, researchers will be able to reserve and utilize the resources in our implementation of this testbed. However, due to the nature of wireless research, we anticipate that other researchers may need an implementation of the testbed on their own campus. Therefore, the majority of this paper describes the details of how we applied, designed, and implemented the framework to provide a versatile testbed. An understanding of the challenges and issues we encountered and resolved will provide insight and guidance to other researchers who plan on implementing this testbed on their campus.

[System Framework]