A system and method to permit efficient communication between multiple devices having different network protocols and to permit a private network device to conduct a direct PPPoE session without restricting other devices on the private network from using another IP address. In particular, a gateway device is provided that translates and routes data packets between devices of different network protocols by referring to a table of device addresses and physical port information. Advantageously, the gateway device may maintain the table dynamically. An entry is created for a device the first time it sends a packet over the network, and an entry is deleted if a device has not sent a packet for a predetermined time interval. If no entry exists corresponding to a packet's destination, the packet is sent to all devices on the network. Finally, the gateway device also identifies the ethertype of data packets and routes them accordingly.