arp or bootp filter applied |
You can see that the motorola device (in my case a moto SB6580) is replying to the DHCP request from my laptop, as well as arping for addresses in the 192.168.0.0/24 network.
Comparing the source MAC address(Ethernet II) for the DHCP reply, or the ARP request to the MAC address of the PC NIC or the cable modem/router MAC address should help you find the offender.