Performance evaluation of RPL objective functions for different sending intervals

IPv6 Routing Protocol for Low Power and Lossy Networks (RPL) is the standard routing protocol for Wireless Sensors Network (WSN). Two main Objective Functions (OF) are used in RPL; Objective Function Zero (OF0) and Minimum Rank with Hysteresis Objective Function (MRHOF), each of these two OFs provides a different way for selecting the parent toward the destination. In RPL, the standard interval for sending one control packet is approximately equal to one minute, this sending interval can be modified to be less than that. The target of this paper is to evaluate the performance of each previously mentioned RPL's OFs with two scenarios. In the first scenario, we fixed the network densities and changed the sending intervals and the transmission range values, and in the second scenario, we fixed the transmission range values, and changed the network densities and the sending intervals. Packet Delivery Ratio (PDR), and power consumption is the considered criteria for this evaluation. The experiments are simulated using Cooja simulator. The results show that there is a clear impact for varying the sending interval on the performance of the RPL's OFs taking in account the network density and the nodes transmission range. In general, increasing sending interval will increase PDR and decrease the power consumption. At the extent of our knowledge, this is the first work that evaluates the RPL objective functions by changing the default sending interval of the control packets taking into consideration the node densities and the transmission ranges.