Middlewares for Smart Objects and Smart Environments: Overview and Comparison

In the last few years, the Internet of Things (IoT) is gaining more and more attention both in the academic and in the industrial worlds. IoT is a concept describing a vision in which everyday objects will be connected to the Internet, will be identified, and will, possibly, communicate with other devices. These objects are typically referred as “smart objects”, which can be defined as real artifacts augmented with computing, communication, sensing/actuation and storing functionalities. Their importance resides in the capabilities they have to make physical environments “smart” so as to provide novel cyberphysical services to people. In the last years, several middlewares for SOs were proposed. Middlewares, widely used in conventional distributed systems, are fundamental tools for the design and implementation of smart objects as well as of smart environment applications. They provide general and specific abstractions (e.g. object computation model, inter-object communication, sensory/actuation interfaces, discovery service, knowledge management) through which smart objects and their related applications can be easily built up. In this chapter, we present an overview of middlewares for smart objects and smart environments and compare them according to the most important general and specific requirements that have been identified in the literature so far. Moreover, such middlewares are also compared according to a feature-oriented framework to better highlight their distinctive properties. The comparison therefore provides a clear picture about the suitability of such middlewares to support the development of SO-based IoT systems. Finally, the chapter will briefly discuss on-going challenges in this research area.