Review of multicast routing mechanisms in mobile ad hoc networks

Frequent interactions among the group members of distributed wireless network environment may be facilitated with the help of Mobile Ad Hoc NETworks (MANETs). Some of the group-oriented applications include disaster management, battlefields, audio/video conferencing, e-commerce, e-education, etc. Group communication demands dynamic construction of efficient and reliable multicast routes under user mobility and varying channel conditions. Multicast routing mechanisms in MANETs have been consistently improved by researchers considering various performance measures such as energy efficient route establishment, packet delivery ratio, quicker and faster proactive route recovery, network life time, reliability, Quality of Service (QoS) based on bandwidth, delays, jitters, and security. The paper focuses on most recent reliable and QoS based multicast routing mechanisms that helps in multimedia communication over MANETs. The mechanisms are considered under different topological routing categories such as mesh, tree, zone and hybrid. We provide an overview of existing multicast routing mechanisms based on routing categories and point to directions for future research and development.