Performance evaluation of RPL on a mobile scenario with different ContikiMAC radio duty cycles

IPv6 Routing Protocol for Low-Power and Lossy Networks (RPL) is the only standardized routing protocol for Low Power and Lossy Networks. Therefore, RPL is the routing protocol chosen for most Internet of Things (IoT) applications. However, the RPL protocol has some open issues when the scenario includes mobile nodes. Since many IoT applications include mobility, this is an important problem to address. Node mobility does not permit the network to stabilize and because of this keep exchanging control messages. Mobility increases the packet loss because mobile nodes may leave the coverage area before transmitting the data. This problems also increase the power consumption. Another important factor affects the RPL performance. To save nodes energy, the data link layer implements a radio duty cycle. These duty cycles turn the radio off when it is not used. One common and used radio duty cycle protocol is the ContikiMAC. Changes in the frequency of the duty cycle modifies the RPL performance. This work shows how the change of radio duty cycle of ContikiMAC on a hybrid scenario, composed by fixed and mobile nodes, interferes on RPL performance. Results show that the nodes mobility degrade the metrics tested. The choice of radio duty cycle is very important to the network performance. The results show that the RPL performance is strictly dependent of the duty cycle.