On Self-Configuring IoT With Dual Radios: A Cross-Layer Approach

Growing interest in emerging IoT applications provides a strong drive to release a plethora of communication radios from different standards, which are largely classified into short-range (IEEE 802.15.4) and long-range radios (IEEE 802.15.4g). In this paper, we propose a joint, self-configuring MAC and routing protocol, SEDA-Net, which aims at adaptively choosing the best configuration for communication coordination and data delivery, depending on different deployed topologies and external conditions. SEDA-Net is a combination of SEDA-MAC, SEDA-Routing, and Cross-Opt. SEDA-MAC and SEDA-Routing adaptively determine the best radio configuration for communication coordination under duty-cycling and each node's next-hop over which radio and Cross-Opt jointly optimizes inter-coupled MAC and routing in an iterative manner. SEDA-Net differs from prior approaches which are designed with static configurations of radios and/or mainly with the goal of throughput maximization for dual Wi-Fi or Wi-Fi/LTE setups. We implement SEDA-Net on Contiki OS and perform extensive simulations and experiments using a testbed in an office building. This testbed consists of 45 nodes equipped with a commercial platform, Firefly, having 2.4 GHz short-range and 920 MHz long-range radios. We demonstrate that energy efficiency quantified by the network lifetime increases by up to 2.1 times, compared to that of existing approaches.

1 Introduction

We are now experiencing the emergence of a plethora of new IoT applications in various domains, e.g., environmental monitoring, surveillance systems, and consumer electronics. They lead a strong drive for a surge of communication radios based on various communication standards with different characteristics. These radios are largely classified into IEEE 802.15.4 [1] at 2.4 GHz1.

It is also known as ZigBee.

and IEEE 802.15.4g [2] at sub-GHz, where the former is characterized by short communication range with high data rate, we call short-range radio, and the latter has long communication range with low data rate, we call long-range radio. We also have a list of products combining both standards with dual radios in the market for flexible operation. These are often called dual-radio motes, including Firefly [3], Waspmote [4], and OpenMote B [5], where we choose Firefly (Fig. 1b) in our testbed (see Section 5 for details).