Adaptive On-Demand Multicast Routing Protocol for Mobile Ad Hoc Networks

Abstract

The On-Demand Multicast Routing Protocol (ODMRP) is a multicast routing protocol for mobile ad hoc networks (MANETs). Its efficiency, simplicity, and robustness against mobility render it one of the most widely used MANET multicast protocols. In this paper, we present an Adaptive On-Demand Multicast Routing Protocol (A-ODMRP), an improved version of ODMRP. ODMRP lacks a control mechanism for the physical layer. Nodes in ODMRP transmit multicast data at a fixed transmission rate and power level for the physical layer. Also, as the number of nodes belonging to the forwarding group increases, there is significant packet drop or retransmission due to interference between the nodes that send multicast data. However, A-ODMRP implements an adaptive control mechanism with a cross-layer algorithm for the physical layer. When a node transmits multicast data, A-ODMRP can adjust the transmission rate and power level of the physical layer to minimize packet drop or retransmission due to interference between nodes belonging to the forwarding group. Simulation results confirmed that A-ODMRP provides an improved goodput of up to 42% compared to ODMRP.