Virtualization of event sources in Wireless Sensor Networks for the Internet of Things

Sensor networks, and more specifically wireless sensor networks (WSN), are generally used to collect information from the environment. The gathered data are mainly delivered to sinks or gateways that become the endpoints where applications can retrieve and use such data. But applications would also expect from a WSN an event-driven operational model, so that they can be notified whenever occur some specific environmental changes instead of analyzing continuously the data provided periodically.In either operational model, wireless sensor networks represent a collection of objects interconnected, in a similar way that is outlined by the Internet of Things vision. In following years sensors will become more capable and resourceful. But in the meantime, they lie into the definition of constrained devices. In addition, to fulfill the vision of the Internet of Things, they must have a virtual representation that allows indirect access to their resources, a model that should also include the virtualization of event sources in a WSN.Thus, in this paper we propose a model for a virtual representation of event sources in a WSN. The event sources are modeled as internet resources that are accessible by any internet application, following an Internet of Things approach. The model has been tested in a real implementation where a wireless sensor network has been deployed in an open neighborhood environment. Different event sources have been identified in the proposed scenario, and they have been represented following the proposed model.