Agent based adaptive multicast routing with QoS guarantees in MANETs

The emergence of multimedia applications demands multicasting in MANETs. For such applications QoS provisioning is a complex and challenging issue. This paper proposes a QoS aware multicast routing scheme uses a set of static and mobile agents and ensures QoS guarantees in terms of bandwidth reservation, delay constraint, delay-jitter constraint and packet loss to multicast session. Here the mobile agents move around the network and collect the routing information. A hybrid method to support an adaptive multipath routing scheme under multiple QoS constraints is introduced. The scheme operates in the following steps. (i) Clustering of nodes and then select the QoS aware cluster heads. (2) Identify and join multicast group members to the backbone. (3) Identify the intermediate nodes and discover multiple paths to satisfy the multiple constraints of a call. (4) Set up a QoS aware path for the required multicast route. (5) Maintain backbone and alternate paths in case of node mobility. Extensive simulations have been conducted to evaluate the performance of the proposed scheme in terms of packet delivery ratio, control overheads and node mobility. The simulation results show that the new scheme performs better than MAODV and ODMRP in terms of reduces the network overhead and improves packet delivery ratio.