A Dynamic Single-Hop Clustering Mechanism Adapted to Overlay Multicast in Mobile Ad hoc Networks

Overlay multicast in mobile ad hoc networks (MANETs) with densely placed member nodes can cause inefficient packet transmission. It is because unicast paths are used in overlay multicast while, in MANETs, broadcast medium is used. Even though the nodes can reach each other within single hop, overlay multicasting creates unicast paths so that in such a case overlay multicast could be very inefficient. In this paper, we propose dynamic single-hop broadcast cluster (SHBC) to solve the problem of overlay multicast. SHBC is a clustering mechanism adapted to overlay multicast in MANETs. SHBC is based on LBC (local broadcast cluster) proposed in efficient end system multicast for mobile ad hoc networks but only constructs clusters in the highly dense areas. Using location information of cluster leaders, frequency of cluster reconstruction in SHBC is reduced around 10% in comparison with LBC