A TCP/IP satellite infrastructure for sensing operations in emergency contexts

The deployment of sensor networks for emergency management must be considered as an irreplaceable support for both monitoring and rescue activities. Depending on the scenario the use of satellite links as a segment of the network ensures connectivity where no other network is available and in some case can also provide an efficient and cost effective means to transfer data. This work aims to define architecture, to identify of optimum solution and to evaluate performance, in terms of throughput and service delay, when a protocol stack - from layer II to layer IV - is considered over a DVB-RCS system. The considered platform is composed of clusters of sensors (including low data rate devices and bulk data cameras) deployed over vast geographical areas, which collect on ground and distribute via satellite multimedia information, i.e. audio, video and sensed data, either for emergency or monitoring operations. A geostationary system was selected in order to guarantee high flexibility in terms of channel capacity. The proposed architecture assumes a session layer protocol, between the transport and application layers, which manages the multiplexing of streams coming from the input sources. The proposed architecture integrates wireless sensor networks and satellite networks, implying to approach technological issues from access layer up to transport and session layers, with heterogeneous traffic sources multiplexed by a satellite gateway, before being encapsulated into TCP/IP flows. Simulation results show the validity of the proposed architecture and protocol solutions.