Information Freshness in Random Access Channels for IoT Systems

This paper introduces and discusses some recent advances in the field of information freshness for Internet of things (IoT) applications. Focusing on a setup in which a large number of transmitters share a common wireless channel to deliver updates to a common receiver, we tackle in particular the role played by random access policies based on variations of the basic ALOHA protocol, employed in most practical IoT systems. The fundamental trade-offs that emerge are discussed together with the enhancement achieved by a number of novel schemes tailored to optimize age of information. The article aims to trigger discussion and further research on a relevant yet still largely unexplored field, and highlights some important issues and challenges that have yet to be addressed.