Patent ID: 7990972

Claim:
A network communication device for forwarding packets between a plurality of user terminal devices and a communication network, the network communication device comprising: a transceiver module configured for forwarding the packets between the plurality of user terminal devices and the communication network; an address translation module configured for receiving the packets forwarded from the transceiver module, determining if destination addresses of the packets forwarded from the transceiver module need to be translated, translating the destination addresses of the packets forwarded from the transceiver module upon the condition that the destination addresses of the packets forwarded from the transceiver module need to be translated, and marking the packets of translated addresses with flags; a control buffer module configured for recording the flags of the marked packets of translated addresses; an internet protocol (IP) routing module configured for receiving the packets from the address translation module and sending the packets from the address translation module back to the address translation module; and a processor that executes the transceiver module, the address translation module, the control buffer module, and the IP routing module; wherein the address translation module determines if the destination addresses of the packets sent back from the IP routing module have been translated by querying the flags in the control buffer module when receiving the packets sent back from the IP routing module, and directly sends the marked packets from the IP routing module to the transceiver module, wherein the address translation module is further configured for releasing the flags from the control buffer module if the address translation module determines the destination addresses of the packets sent back from the IP routing module have been translated.