A two-tier hierarchical network for adverse events monitoring

In this paper we propose a flexible two-level architecture for wireless communications in areas where the deployment of wired networks is not feasible, as in disaster recovery scenarios. The first layer of communication guarantees medium-range transmission, being based on the IEEE 802.11s draft for Mesh Networking. The lower one is instead optimized for short-range, low-power communication between sensor and actuator nodes, most of which are battery-powered. The system architecture and related features are described in detail, and some preliminary experimental results of the subsystems are presented.