Improving performance of route maintenance processes in RPL protocol

Currently, there is a rapid increase in the implementation of Internet of Thing (IoT) systems in many areas such as smart building, and smart cities. This type of network has different sets of requirements than other network types. It needs to effectively work with unreliable wireless channel condition. IETF proposed IPv6 Routing Protocol for Low-Power and Lossy Networks (RPL) for addressing lossy environment problem. However, many important mechanisms of RPL protocol are underspecified. In this paper, we examine the performance of the route maintenance processes that are provided in RPL protocol (the combination of Neighbor Unreachability Detection Mechanism (NUD), Objective Function Zero (OF0) and The Minimum Rank with Hysteresis Objective Function (MRHOF)). Both practical and simulation experiments are conducted. The results from the practical experiments shows that the performance in term of Packet Reception Ratio from the combination between NUD and MRHOF is better than the combination between NUD and OF0. Moreover, the simulation experiments are also conducted to explore the best approach to improve the route maintenance processes by modifying two parameters in NUD and MRHOF mechanisms. The results from the simulation experiments indicate that when the data rate is low, modifying the value of the parameter in MRHOF can significantly improve the performance of the route maintenance processes but the careful consideration is required.