Smart Systems and IoT: Innovations in Computing

Abstract

Several sensing devices with actuating capabilities communicate with each other which are connected to the internet that enable variety of application such as smart city, smart building, smart agriculture, etc. form Internet of Things (IoT). Resource constraints are part of IoT networks. These devices and networks are low on energy, processing power, memory and data rate. In 2012, IETF ROLL working group published in RFC 6550, which specifies Routing Protocol for Low Power and Lossy Networks (RPL). RPL was designed for efficient and reliable data collection in low power and lossy networks. RPL based network is constructed using Destination Oriented Acyclic graph (DODAG) for data forwarding and network management. Load balancing in RPL is an important concern. Due to uneven deployment of sensor nodes in large areas, and the heterogeneous traffic patterns in the network, some sensor nodes may have much heavier workload in terms of packet forwarding than others. Such unbalanced workload distribution will result in bottle neck of parent node, frequent parent switching, sensor nodes quickly exhausting their energy, and shorten the overall network lifetime. In this paper, we propose Child Count based Load Balancing in RPL namely Ch-LBRPL. Ch-LBRPL detects load imbalance at DAG, DODAG and Multi DODAG level and uses child count method to overcome load imbalance. The results suggest that Ch-LBRPL is efficient in load balancing DAG and DODAGs, reduce parent switching, reduce DIO messages and improve energy efficiency. We also propose new model for Multi DODAG load balancing.