Through the information network recovery experience on the East Japan Great Earthquake on March 11, 2011, we learned that the combination of various existing wireless network technologies such as satellite IP network, 3G/LTE, Wi-Fi was useful in term of network connectivity. In this paper, by integrating those wireless networks into a cognitive wireless network, user can use this cognitivenetwork as an access network to Internet by selecting the best performance network among the possible network links even though the serious disaster occurred and some of those network links were seriously damaged.
We also introduce an Open Flow based access network to automatically control link and route selections within the cognitive wireless network to Internet by periodically monitoring and evaluating their network states. In order to verify the usefulness of our proposed system, a prototype of Open Flow based cognitive wireless network system is constructed by connecting the disaster areas in the East Japan Great Earthquake and its performance is evaluated.