Flow processing-aware controller placement in wireless DenseNets

The traffic demand in wireless access networks has grown substantially in recent years and is expected to continue doing so, both in terms of total volume and data rate required by individual users. To overcome the current limitations of wireless access networks, operators already push for very dense and heterogeneous wireless networks, commonly known as DenseNets. Efficiently controlling DenseNets is a task for current research, as simply scaling existing networks by orders of magnitude brings along several problems, e.g. increased energy consumption and the explosion of signaling. Further, new innovations such as Network Functions Virtualization (NFV) which target the operation expenses for networks with a large variety of proprietary hardware appliances, reveal that data flow processing should not be neglected in this research domain. Software-Defined Networking (SDN), which separates the control plane and the data forwarding plane, has been identified as a promising approach for an efficient control of DenseNets. However, the controllers of classic SDN approaches are confined to the routing of data flows, while the support of sophisticated processing mechanisms, e.g. NFV or Coordinated Multi-Point transmission (CoMP), is not considered. Data flow processing imposes many requirements on data rate, latency and processing capacity. Hence, an adequate allocation of the locations for data processing in a network is a challenging task and crucial for network performance. In this paper we propose our flow processing-aware controller placement framework that takes into account data flow processing and control applications, both enhancing the SDN architecture specifically for DenseNets.