Disaster messenger: An android based infrastructure less application for post disaster information exchange

Natural disasters take its toll on traditional communication infrastructure severely causing intermittent network connectivity due to partially or fully damaged communication infrastructure. Therefore, data dissemination is hampered and the volunteers and different disaster management agencies find it difficult to communicate among them. Fortunately, a sizeable population (around 35%-45%) these days owns various wireless devices like smart phones, tablets etc. with multiple communication interfaces (Bluetooth, Wi-Fi Direct). These devices with their alternative communication capabilities can be harnessed in a disaster aftermath in order to disseminate situational information. However, the procedure to disseminate such information through these devices should be simple enough so that minimal technical expertise is required from the user end. Several Android based applications are available which offers data forwarding service based on Wi-Fi direct. All such applications provide only unicast mode of communication while lacking to provide multicast and broadcast services. In this paper we provide a complete solution Disaster Messenger, an Android based application which allows the volunteers to disseminate information in absence of network infrastructure (through Wi-Fi direct) in unicast, multicast and broadcast mode. We perform rigorous field experiments to evaluate the performance of Disaster Messenger by varying movement speeds of the nodes and distance between the nodes. We also evaluate its performance in terms of energy efficiency. The comparison of the Disaster Messenger with a couple of well-known file sharing applications namely SHAREit and BitTorrent Sync reveals that Disaster Messenger outperforms SHAREit and BitTorrent Sync in terms of energy efficiency and data transfer rate in unicast mode. Due to unavailability of any competing application which supports multicast and broadcast services, we have not been able to compare the performance of our application for the said services.