A proposal of disaster-risk-aware network routing control method and its evaluation

Most of public organizations and medical institutions make backup copies of their important data, such as residential and medical information, to local servers, remote servers, and cloud systems. However, when a major disaster strikes, it may cause serious damages not only on the local servers but also on network links to the remote servers and cloud systems. In such cases, we lose the local backup data, and besides, we have no access to the remote backup data for a while. The experience of the Great Eastern Japan Earthquake reminds us of the importance of another backup approach which transfers important data to low-risk servers in the neighborhood immediately after a disaster. To realize this backup approach, we propose a novel risk-aware smart routing scheme. For achieving effective data transmission in a time of disaster, the proposed scheme controls data routes dynamically according to the disaster risks of nodes and links in the network as well as the changing status of the network. This paper presents its detailed design and implementation by using Software Defined Network (SDN) technology. We evaluate the effectiveness of our scheme through the simulation experiments and confirm that it can achieve effective data transmission.