The Internet of Things on Its Edge: Trends Toward Its Tipping Point

In this article, a review of commercial devices on the edge of the Internet of Things (IoT), or IoT nodes, is presented in terms of hardware requirements. IoT nodes are the interface between the IoT and the physical world (e.g., sensor nodes). To this aim, we introduce a wide survey of existing devices made publicly available for the further analysis of trends and state of the art. This data-driven approach permits developing quantitative insight into the big picture of the current status of IoT nodes. The analysis shows that an order (ultimately two orders) of magnitude gap needs to be filled in terms of size, lifetime, and cost (energy efficiency) to ultimately make IoT nodes truly ubiquitous and trigger the widely expected exponential growth of the IoT ecosystem. Overall, this article presents a view from the edge of the IoT and a glimpse of its tipping point.