Comparison of Data-Driven Link Estimation Methods in Low-Power Wireless Networks

Link estimation is a basic element of routing in low-power wireless networks, and data-driven link estimation using unicast MAC feedback has been shown to outperform broadcast-beacon based link estimation. Nonetheless, little is known about how different data-driven link estimation methods affect routing behaviors. To address this issue, the authors classify existing data-driven link estimation methods into two broad categories: L-NT that uses aggregate information about unicast and L-ETX that uses information about the individual unicast-physical transmissions. Through mathematical analysis and experimental measurement in a testbed of 98 XSM motes (an enhanced version of MICA2 motes), they examine the accuracy and stability of L-NT and L-ETX in estimating the ETX routing metric.