Patent attributes
Redundant gateway methods, apparatus and systems using more than one gateway device in a gateway device group for communications directed outside of a LAN. Failover services are thus provided in the event that an active router or other gateway device fails. Network address translation (NAT) services are provided simultaneously by having all gateway devices in the redundancy group create and maintain IP aliases and static NAT mappings, while disabling all gateway devices operating in a non-active mode from replying to address resolution protocol requests from hosts. A gateway device may be configured to operate in a redundancy group in an active operating mode or a non-active operating mode. The gateway device handles transmissions into and out of the network to which it is connected only when the gateway device is in the active operating mode so as to avoid system corruption due to ARP activity and message transmissions by non-active gateway devices.
