Wireless Multicast Cross-Layer Framework for Rate Allocation: Protocol Design

Multicast-based data communication is an efficient communication scheme especially in multihop ad hoc networks where the MAC layer is based on one-hop broadcast from one source to multiple receivers. In this paper, we discuss a framework of rate allocation for a set of multicast sessions over multihop wireless networks. We propose a framework that facilitates the online calculation of the optimal rates for a set of multicast sessions such that the aggregate utility for all sessions is maximized. This framework is used to steer the entire network of ad hoc nodes towards the optimal point in real time using a totally distributed and asynchronous environment settings. We present a series of implementations based on different network settings and show that not only convergence to the optimal rates is attained in all these network settings but also network changing conditions such as mobility and dynamic channel capacity can be tracked in real time.