| 摘要 |
PROBLEM TO BE SOLVED: To grasp the connection relationship between each communication device included in a communication network subordinate to a router, such as a LAN (local area network), at low costs without burdening an excessive load upon the communication device.SOLUTION: A switching hub, receiving from the downstream side an ARP (Address Resolution Protocol) packet destined to a router for connecting a LAN to an IP network, is allowed to execute processing to add to the ARP packet and transfer tag information indicative of a port that receives the ARP packet. The router, when receiving an ARP packet destined to the self-router, is allowed to execute processing to generate, from the tag information added to the ARP packet, and store information indicative of the connection relationship between the communication terminal of the transmission source of the ARP packet and a switching hub on the transfer route of the ARP packet. |
