An overview of opportunistic ad hoc communication in urban scenarios

In the era of the Internet of Everything, users with handheld or wearable devices equipped with sensing capability have become producers as well as consumers of information and services. The more powerful these devices get, the more likely it is that they will generate and share content locally, through ad hoc opportunistic connectivity, leading to the presence of distributed information sources and forwarders and the diminishing role of centralized, infrastructure-based servers. Despite this interesting portrait, the mobile and volatile nature of this network presents severe challenges demanding new networking techniques able to cope with the unpredictable and resource-constrained nature of mobile entities comprising it. In this context, we discuss novel data gathering and dissemination strategies in urban scenarios which do not rely on strict infrastructure mediation. While preserving the general aspects of our study and without loss of generality, we focus our attention toward practical applicative case studies which help us capture the characteristics of ad hoc opportunistic communication networks, and devise efficient solutions for use in real applicative contexts.