Experiments with the MOST multicast protocol in a wireless multi-hop network

In this article, we describe experiments with the multicast protocol MOST (Multicast Overlay minimum Spanning Tree) on a real testbed. The testbed is a wireless multi-hop network with nodes running a MANET protocol, the OLSRv2 routing protocol, and with IEEE 802.11g hardware. We present our specification and implementation of MOST for OLSRv2. Its main feature is to build an (unicast) overlay tree covering members of a group. Through different scenarios and applications such as voice and video, we evaluate MOST performance in term of average packet delivery ratio, jitter and pay a particular attention to the MAC layer statistics. We also evaluate qualitatively and quantitatively the improvements brought by MOST compared with MPR flooding (an optimization of a pure flooding proposed and used in OLSR).