Patent ID: 8239506

Claim:
A method for affecting the behavior of a network device, the network device comprising at least a processor and the method comprising: creating at the network device a lease renewal request message requesting renewal of an IP address lease, wherein the network device is connected to a cable modem; directing the renewal message from the network device through the cable modem to a cable modem termination system (CMTS); inserting at the CMTS the cable modem MAC address into the renewal message; sending the lease renewal request message to a dynamic host configuration protocol (DHCP) server from the CMTS; accessing from the DHCP server a configuration record associated with the network device in response to the presence of the modem MAC address in the lease renewal request message; determining by the DHCP server using the modem MAC address whether the configuration record comprises a quarantine attribute field; determining an attribute value assigned to the quarantine attribute field when the quarantine attribute field is present in the configuration record; renewing the lease of the network device and assigning an address of an external DNS server in a lease renewal response message when the quarantine attribute field is not present in the configuration record; assigning an address of a quarantine DNS server to a DNS IP address option in a lease renewal response message when the attribute value is a first value; and sending the lease renewal response message to the network device through the cable modem, wherein in response to the lease response message, a DNS query sent from the network device is directed to the quarantine DNS server when the address of the quarantine DNS server is assigned in the lease renewal response message.