RADIator — An approach for controllable wireless networks

In this paper we propose a novel software-defined networking architecture for enterprise wireless local area networks (WLANs). The goal is to build a framework that exposes tools and methods for a centralized processing of IEEE 802.11 frames. In our architecture all management tasks, including beaconing, client authentication and association, are performed by the central controller instead of the distributed wireless access points as in traditional networks. The generated frames are tunneled to lightweight wireless access points (APs) or thin APs that perform the media access and radio frequency (RF) conversion. Agents executed on thin APs allow scheduling of simple tasks like traffic filtering for local execution. Additionally, the agents provide functions found in modern WLAN chipsets, such as precise frame transmit timings or RF spectrum analysis to the controller. Our architecture allows to delegate computationally intensive tasks to a central instance with enough processing power. Thus, it is best suited for devices with limited resources that we use as thin APs. We present applications that can be built using our framework, e.g., client geolocalization or energy consumption optimization. Finally we evaluate the performance of our architecture in a testbed using COTS devices with open-source software.