DIO messages and trickle timer analysis of RPL routing protocol for UAV-assisted data collection in IoT

Routing protocol for low-power and lossy networks (RPL) is an widely-used IPv6 routing protocol for lossy wireless networks with the power constrained devices in Internet of Things (IoT). It is a proactive protocol that constructs a destination oriented directed acyclic graph (DODAG) rooted at the single destination called the root node that resides at unmanned aerial vehicle (UAV). Specifically, a DODAG is built with the help of different control messages like DODAG information object (DIO), DODAG advertisement object (DAO), and DODAG information solicitation (DIS). As the generation of these messages incur additional energy consumption, RPL uses the Trickle algorithm to dynamically adjust the transmission windows. In this paper, we analyze the effect of the two parameters, namely, DIO-INTERVAL-MINIMUM and DIO-INTERVAL-DOUBLING that have significant effect on the Trickle algorithm and the rate of message generation. Through experiments, we show that an optimal selection of these parameters saves a significant amount of energy with different parameter settings in UAV-assisted IoT networks.