Impact of LQI-Based Routing Metrics on the Performance of a One-to-One Routing Protocol for IEEE 802.15.4 Multihop Networks

The quality of an IEEE 802.15.4 link can be estimated on the basis of the Link Quality Indication (LQI), which is a parameter offered by the IEEE 802.15.4 physical layer. The LQI has been recommended by organizations such as the ZigBee Alliance and the IETF as an input to routing metrics for IEEE 802.15.4 multihop networks. As these networks evolve, one-to-one communications gain relevance in many application areas. In this paper, we present an in-depth, experimental study on the impact of LQI-based routing metrics on the performance of a one-to-one routing protocol for IEEE 802.15.4 multihop networks. We conducted our experiments in a 60-node testbed. Experiments show the spectrum of performance results that using (or not) the LQI may yield. Results also highlight the importance of the additive or multiplicative nature of the routing metrics and its influence on performance.