STEM-Net: an evolutionary network architecture for smart and sustainable cities

The concept of smart city has emerged worldwide as a feasible answer to the challenges raised by the increasing urbanisation. From the technological point of view, guaranteeing ubiquitous connectivity, reliable communications and seamless integration of multiple network access technologies are mandatory in a smart city. This is in contrast with the current infrastructure deployment in several urban areas, which is characterised by lack of ubiquitous connectivity and coverage and by fragmentation of networks that are usually deployed by different operators and without any centralised control by the city authorities. In this paper, we look at the heterogeneity of devices and network technologies under a different perspective by not perceiving it as a limitation but as a potential to increase the connectivity in a smart city. We propose a new generation of network nodes, called stem nodes, based on the innovative idea of ‘stemness’, which pushes forward the well-known self-configuration and self-management concepts towards the idea of node mutation and evolution. We also deployed prototypes that demonstrate the stem-node architecture and basic operations in different hardware platforms of common communication devices (an Alix-based router, a laptop and a smartphone).