4. Troubleshooting

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In segments monitored by NetSkateKoban Sensor, there are terminals that rarely appear on the map even though they are connected to the network.

NetSkateKoban Sensor detects terminals by receiving ARP and DHCP packets sent by the terminals.

When an unauthorized terminal connects to the network, it always sends DHCP or ARP packets before communicating, so connection detection and blocking are performed without issue.

However, devices that are constantly connected to the network—such as terminals that do not communicate at all or communicate almost exclusively via the default gateway (e.g., thin clients), NAS servers, printer servers, and intelligent L2 Ethernet switches—tend not to send ARP packets. As a result, they may not appear on the network map.

If you wish to constantly detect and display the network connection status of such devices, please use the NetSkateKoban Sensor's "Active Detection Function".

By using this function, the Sensor periodically sends ARP requests to the configured IP address range, ensuring that even terminals with the characteristics described above are reliably detected and displayed.