A Virtual Network Approach for Testing Wireless Mesh in Industrial Process Control

Unlike wired networks, the configuration and the behavior of wireless networks are heavily dependent on many environmental factors. While this makes it more difficult to build a wireless network testbed whose behavior is controllable, it also makes the availability of such a testbed all the more desirable. Indeed, the difficulties in building a good wireless mesh testbed belie the fact that most research work on mesh network performance is backed up only by computer simulations. In this paper, we present a practical design philosophy in which a realistic and controllable wireless mesh network testbed is built with a relatively small deployment of physical equipments by exploiting the idea of a virtual network. Specifically, we simulate a virtual network within the testbed and use one physical wireless transceiver to simulate multiple virtual devices. An observer who only reads the transmitted wireless messages will not be able to tell the difference from a real wireless mesh. Our approach has been adopted in a recent industry-standard testing suite, namely, Wi-HTest. In this paper, we shall discuss our experience in building Wi-HTest by applying the virtual network approach.