Efficient Real–time Content Distribution for Multiple Multicast Groups in SDN–based WLANs

Wireless network research and development efforts are largely driven by the increasing interest in multimedia applications. Video streaming services, which often involve strict quality of service requirements and are very sensitive to delays, represent a significant proportion of these applications. In IEEE 802.11-based WLANs, these services raise several challenges in terms of robustness, reliability, and scalability, especially when supporting multiple multicast streams at the same time. Nevertheless, traditional network architectures make it difficult to address these problems. In this context, the software defined networking (SDN) paradigm opens new research possibilities by decoupling the control decisions from the data-plane and by improving network management and programmability. In this paper, we present SM-SDN@Play, an SDN-based solution for joint multicast rate selection and group formation in 802.11-based networks. Experimental results show the high performance and reliability capabilities of the scheme, regardless of the application bitrate, the number of clients, and the number of concurrent multicast streams. Furthermore, the channel utilization is greatly reduced with regard to the standard multicast schemes, which allows other applications to be supported without experiencing a performance degradation. We release the entire software implementation under a permissive APACHE 2.0 license for academic use.