Performance Evaluation of PC Router Based Cognitive Wireless Network for Disaster-Resilient WANs

In order to temporally recover the information network infrastructure in disaster areas on the East Japan Great Earthquake on March 11, 2011, various wireless network technologies such as satellite IP network, 3G, Wi-Fi were effectively used. However, since those wireless networks are individually introduced and installed, but not totally integrated, some of networks were congested due to the sudden network traffic generation and unbalanced traffic distribution, eventually the total network could not effectively function. In this paper, by integrating those wireless networks into a cognitive wireless network, user can use this cognitive network as an access network to Internet by selecting the best network even though the serious disaster occurred. We introduce an OpenFlow based access network to automatically select the best network link and route among the possible access networks to Internet by periodically monitoring their network states and evaluate the those using extended AHP method. In order to verify the usefulness of our proposed system, a prototype system is constructed and its performance is evaluated.