  Multicast communication plays a crucial role in Mobile Adhoc Networks
(MANETs). MANETs provide low cost, self configuring devices for multimedia data
communication in military battlefield scenarios, disaster and public safety
networks (PSN). Multicast communication improves the network performance in
terms of bandwidth consumption, battery power and routing overhead as compared
to unicast for same volume of data communication. In recent past, a number of
multicast routing protocols (MRPs) have been proposed that tried to resolve
issues and challenges in MRP. Multicast based group communication demands
dynamic construction of efficient and reliable route for multimedia data
communication during high node mobility, contention, routing and channel
overhead. This paper gives an insight into the merits and demerits of the
currently known research techniques and provides a better environment to make
reliable MRP. It presents a ample study of various Quality of Service (QoS)
techniques and existing enhancement in mesh based MRPs. Mesh topology based
MRPs are classified according to their enhancement in routing mechanism and QoS
modification on On-Demand Multicast Routing Protocol (ODMRP) protocol to
improve performance metrics. This paper covers the most recent, robust and
reliable QoS and Mesh based MRPs, classified based on their operational
features, with their advantages and limitations, and provides comparison of
their performance parameters.
