Date Added: Apr 2011
In the actual disaster case, there is a certain possibility that electric power line is damaged and power energy cannot be supplied to those communication network devices, and eventually those wireless LANs cannot be functioned. Although mobile wireless network is easy to reconstruct than wired network, there may be the case that network disconnection is not affordable after disaster. That is, Disaster Information System needs a robust Never Die Network (NDN) which will be unaffected by any changes in environment after severe disaster. Satellite Network System is one of possible solution for such a severe disaster, but it has some problems like low throughput, large latency, high cost, and so on.