Software Defined Mobile Multicast

Mobile multicast has been deployed in telecommunication networks for information dissemination applications such as IPTV and video conferencing. Recent studies of mobile multicast focused on fast handover protocols, and algorithms for multicast tree management have witnessed little improvement over the years. Shortest path trees represent the status quo of multicast topology in real-world systems. Steiner trees were investigated extensively in the theory community and are known to be bandwidth efficient, but come with an associated complexity. Recent developments in the Software Defined Networking (SDN) paradigm have shed light on implementing more sophisticated protocols for better routing performance. We propose an SDN-based design to combat the complexity vs. Performance dilemma in mobile multicast. We construct low-cost Steiner trees for multicastin a mobile network, employing an SDN controller for coordinating tree construction and morphing. Highlights of our design include a set of efficient online algorithms for tree adjustment when nodes arrive and depart on the fly, and an SDN rule update framework based on constraints expressed by boolean logic to ensure loop free rule updates. The algorithms are proven to achieve a constant competitive ratio against the offline optimal Steiner tree, with an amortized constant number of edge swaps per adjustment. Mininet-based implementation and evaluation further validate the efficacy of our design.