OFM: A Novel Multicast Mechanism Based on OpenFlow
Yang Yu, Qin Zhen -, Xin Li, Shanzhi Chen · INTERNATIONAL JOURNAL ON Advances in Information Sciences and Service Sciences · 2012
IP multicast is resource efficient in delivering data to a group of members simultaneously. However, in the current multicast architecture, the routers need to be involved both in forwarding multicast packets and multicast management, which arouse a lot of control overhead and add substantial complexity to the router. Large numbers of multicast groups result in large amount of state to be maintained at routers, which means lots of message exchange between routers and slow packet forwarding. In additions, the dynamic receiver join or leave also increases the complexity of management for multicast router. This paper proposed a novel multicast mechanism based on OpenFlow, called OpenFLow Multicast (OFM). OFM separate the data and control plane by shifting the multicast management to a remote centralized controller, and the routers (named as forwarders in OFM) are used as a forwarding engine only. The centralized controller is a core part in OFM multicast, which is responsible for handling the member request, constructing the multicast tree, and multicast state maintenance. Forwarders forward the multicast packet based on multicast routing entries which were generated by the centralized controller. Compared with traditional multicast, OFM can alleviate the burden of multicast routers and also accelerate the router’s packet forwarding speed. Simulation and experiment results demonstrate that OFM has a good performance.