MEGCOM: Minimum-Energy Group COMmunication in Multihop Wireless Networks

Given the increasing demand from wireless applications, designing energy-efficient group communication protocols is of great importance to multihop wireless networks. A group communication session involves a set of member nodes, where each of them needs to send a certain number of data packets to all other members. In this paper, we consider the problem of building a shared multicast tree spanning the member nodes in static wireless networks such that the total energy consumption of a group communication session using the shared multicast tree is minimized. Since this problem was proven as NP-complete, we propose, under our Minimum-Energy Group COMmunication (MEGCOM) framework, three distributed approximation algorithms with provable approximation ratios. When the transmission power of each wireless node is fixed and identical, our first two algorithms have the approximation ratios of O(ln(Δ + 1)) and O(1), respectively, where Δ is the maximum node degree in the network. When the transmission power of each wireless node is adjustable, our third algorithm again delivers a constant approximation ratio. We also use extensive simulations to verify the performance of our algorithms.