EE-OLSR: Energy Efficient OLSR routing protocol for Mobile ad-hoc Networks

This paper presents two novel mechanisms for the OLSR routing protocol, aiming to improve its energy performance in Mobile ah-hoc Networks. Routing protocols over MANET are an important issue and many proposals have been addressed to efficiently manage topology information, to offer network scalability and to prolong network lifetime. However, few papers consider a proactive protocol (like OLSR) to better manage the energy consumption. OLSR presents the advantage of finding a route between two nodes in the network in a very short time, thanks to its proactive scheme, but it can expend a lot of resources selecting the MultiPoint Relays (MPRs) and exchanging Topology Control information. We propose a modification in the MPR selection mechanism of OLSR protocol, based on the Willingness concept, in order to prolong the network lifetime without losses of performance (in terms of throughput, end-to-end delay or overhead). Additionally, we prove that the exclusion of the energy consumption due to the overhearing can extend the lifetime of the nodes without compromising the OLSR functioning at all. A comparison of an Energy-Efficient OLSR (EE-OLSR) and the classical OLSR protocol is performed, testing some different well-known energy aware metrics such as MTPR, CMMBCR and MDR. We notice how EE-OLSR outperforms classical OLSR, and MDR confirms to be the most performing metric to save battery energy in a dense mobile network with high traffic loads.