Improvement of On Demand Multicast Routing Protocol in ad hoc networks to achieve good scalability and reliability

An ad hoc network is a dynamically reconfigurable wireless network with no fixed wired infrastructure. The primary concerns in ad hoc networks are bandwidth limitation and unpredictable dynamic topology. Reliable Multicast plays a significant role in many applications of Mobile Ad Hoc Networks (MANETs). The On-Demand Multicast Routing Protocol (ODMRP) was designed for multicast routing in ad hoc networks. In this paper, we propose a cluster-based on demand multicast routing protocol to the lack of extension of flat multicast routing protocols in ad hoc networks of large scale. Simulation results show that using clustering base ODMRP improves network performance in terms of end-to-end delay and control packets. Also we propose a local recovery approach to design a reliable multicast algorithm. By this approach nodes can join to multicast groups in short time and data delivery will be increase, so ODMRP transmits the data with good reliability.