A Reliable and Delay-Aware Routing in RPL

In the Internet of Things (IoT), collecting and transferring data of edge devices is very important. IoT Devices are often heterogamous and resource constrained. Therefore, in multi-hop communications at the edge of the network, a reliable routing protocol is required. Routing Protocol for Low Power and Lossy Networks (RPL) was designed by IETF-ROLL, which is a particular routing protocol for Wireless Sensor Networks (WSN) especially Low-Power and Lossy Networks (LLNs). In many real-time applications such as healthcare, low latency transfers are vital. Furthermore, devices deployed in LLNs often communicate with medium-quality radio links that can be disconnected and lead to packet loss. Considering these limitations, we propose some changes in RPL to make a Reliable and Delay Aware RPL (RDARPL) protocol. We add a new metric named ETXDHC that consists of Expected Transmission Count (ETX), hop count, and delay. The performance of RDARPL evaluated by COOJA simulator. Experimental results show that the performance of RDARPL was promising in terms of qualitative parameters such as end-to-end delay, Packet Delivery Ratio (PDR), throughput and energy consumption.