Solutions to Support Mobility in SDN-Based Dense Wireless Networks

The software-defined networking (SDN) concept is an efficient solution to manage highly complex wired networks, such as large-scaled data centers and fixed Internet network. The basic idea of SDN is to separate the control and data forwarding functions of routers so that the traffic engineering (TE) optimization can be dynamically made by a central controller. However the application of SDN concept in dense wireless networks is not straightforward. Unlike wired networks, the channel capacity of wireless networks always changes, depending on the mobility of users, channel fading and interference. In dense wireless networks with mobile users, the impacts of varying channel capacity are more difficult to handle because of small cell size. In this paper, we propose SDN-based integrated solutions to support user mobility in dense wireless networks. Our solutions include traffic engineering, dynamic placement of virtual user gateway, and fountain coding. Our simulation results from a SDN-based simulator show that our solutions bring remarkable gains compared with conventional solutions.