A Decentralized SNS System Based on XMPP with Connection Control in Large-Scale Disasters

Abstract

SNS websites and messages have become a regular part of daily life. However, some large-scale disasters such as earthquakes could damage network cables and equipment and cause network failures. Despite the assistance of information related to disasters and support that is effective for controlling the situation and offering help, it is possible that frequently used SNS messages and websites will become unreachable in a disaster area. Moreover, in a disaster area, the network could break into several sub-networks because of the damage of the backbone network. It is possible that the sub-networks can provide network services in a smaller area range without connecting to the Internet. Therefore, this paper proposes a decentralized SNS system that could solve two major problems during large-scale disasters. First, it describes a stable and continuous SNS network for the affected population and helpers without the influence of networks in the disaster region. Second, it proposes a reliable method to share synchronized data across the affected areas. In this case, a reliable method to control connections among shelters, whether newly built shelters or shelters that lost connection during the disaster, should also be considered. This paper shows the effectiveness of the proposed decentralized SNS system using XMPP to provide SNS for refugees and helpers in each shelter under an emergency of network failure. The connection control among shelters has also been examined and was designed to provide secure connections and data synchronization for this decentralized SNS system.