Performance assessment of the routing protocol for low power and lossy networks

Abstract

RPL (IPv6 Routing Protocol for Low Power and Lossy Networks) is proposed by the ROLL working group at IETF. This protocol used in the Internet of Things is optimal for Low power and Lossy Networks (LLNs). However, the RPL network has some limits when the network is dense. In this paper we evaluate the performance of RPL in three different scenarios. We first, evaluate the characteristics of RPL with fixed nodes, (one sink and others are senders). Then we add mobility, and we compare mobile nodes to fixed nodes in order to show how mobility can influence protocol parameters. Finally, we study the behavior of RPL when the network is dense in order to assess the protocol performances. In this study, we use Contiki OS and Cooja software for all simulations. The results show that RPL performances are greatly influenced by the number of nodes, type of mobility and the topology of the network. When the number of nodes increases, all metrics increase too, especially the power consumption which arrives until an augmentation of 52,85%. Furthermore, Random Waypoint Mobility Model (RWP) gives better metrics than Random Walk (RWK) Mobility Model in terms of number of hops and Expected Transmission (ETX) value. Also, in RWP model, nodes consume 10,73% of power than RWK. Our simulations show clearly that the power consumption is directly related to the number of sink nodes in the network. The more this type of node is present in the network the less power is consumed. The power reduction may occur till 5%.