CRRP: A cooperative relay routing protocol for IoT networks

Wireless communication is increasing along with improvements in chipset performance. New applications associated with the Internet of Things (IoT) often involve self-organization and collaboration among many autonomous wireless devices for which traditional infrastructure-based wireless networks are not suitable. Mobile Ad hoc Networks (MANETs), with their infrastructure-less, spontaneous and arbitrary multi-hop features are considered a popular approach for such scenarios, although they also face certain inherent challenges. These include: the limited communication range of each mobile node, power supply restrictions and frequent link breaks due to node movements. In this paper, in order to address the lack of a systematic cooperative routing scheme, we propose a novel protocol called Cooperative Relay Routing Protocol (CRRP) for data transmission in MANETs. Since node mobility can cause frequent radio link breaks, one of CRRP's pivotal design features is to enhance resilience, therefore improving the overall network throughput. This is achieved by forming localised cooperative (COP) topologies where appropriate. Furthermore, as nodes are often battery-powered, CRRP reduces the energy consumption when packets are forwarded by exploiting cooperative diversity. We assess the performance of CRRP via simulations and the results confirm its favorable operation compared to both classic and newer energy-aware MANET routing protocols.

I. Introduction

Currently, most wireless communication is based on cellular and Wireless Local Area Networks (WLANs). However, these are effectively point-to-point in nature and provide “last hop” communication between a mobile device and a wired infrastructure. Recent wireless applications can involve and benefit from machine-to-machine self-organized communication. For example, portable mobile devices in IoT can act as smart sensors, relays and data-processing units, providing distributed intelligent services. This requires the construction and maintenance of a communication network without any outside support, in spite of random device mobility. These conditions are unsuitable for current infrastructure-based cellular/\WLAN networks. Mobile Ad hoc Networks (MANET) [1], with infrastructure-less, spontaneous and arbitrary multihop features are recognized as a promising solution for these scenarios. However, MANETs also face certain inherent challenges: the limited communication range of each mobile node, the restricted power supply and the possibility of link breaks due to frequent node movements. Many studies have been carried out in recent years to address these difficulties from different perspectives. Among these, cooperative communication has received much attention due to its perceived benefits, such as lower power consumption, reduced interference and potential channel diversity gain.