| （英） |
As a part of countermeasure against cyber attacks targeting vulnerabilities of IoT devices without enough security level, network scan on entire internet to find such vulnerable IoT devices is important. However, if the existing network scan technology is applied to wireless networks, it causes a large amount of wireless traffic and severely degrade quality of service of data traffic transmitted by IoT devices. To overcome this issue, it is necessary to conduct network scan when wireless networks are not congested so as to prevent collisions and retransmissions. On the other hand, the server conducting the network scan via the Internet cannot know the status of the wireless networks. In order to grasp the status of the wireless networks, in this presentation, we propose a method to estimate the number of wireless retransmissions as a metric of network status. In the proposed method, the distribution of scan response delay according to the number of wireless retransmissions is obtained by preliminary computer simulation, and then the number of wireless retransmissions is estimated from scan response delay and the obtained distribution of them. |