Understanding the Design Space of a Software Defined WiFi Network Testbed

Due to the simple technical implementation, lowcost network construction and high-bandwidth wireless link capacity, WiFi networks have become popular in the last decade. Nevertheless, WiFi networks have still facing various technical challenges such as load balancing, mobility support and channel adaptation. The emerging software defined networking (SDN) has now been proposed to address the above issues in WiFi networks. SDN provides flexible network management by separating control and data plane, in which some network management entities are able to control the whole network in a unified way. This centralized management provides potential coordinations between access points. In this paper, we study advantages and drawbacks of different approaches for controlling aWiFi network testbed. Our testbed consists of a single controller, multiple access points with up to 24 end-hosts. The evaluation scenarios include single and multiple basic service sets. The performance metric focuses on network throughput with different loads. Our results demonstrate the trade-off between network performance and control flexibility in the current software defined WiFi testbed. Our study may lead to deeper insights into understanding the design space of the software defined WiFi network and the potential directions for the performance optimization.