Redundant internet protocol gateways using local area network emulation

摘要

An ELAN having redundant default gateways is attached to an asynchronous transfer mode (ATM) communications network. The ELAN's redundant default gateways are comprised of a first and second routers. The first router is associated with a primary default gateway and the second router is associated with a backup default gateway. Both the primary and backup default gateways are connected to the ELAN and both the primary and backup default gateways are configured with a default gateway IP address and associated MAC address. Initially, the primary default gateway registers the default gateway MAC address, thereby becoming the active default gateway. While the primary default gateway is active, the backup default gateway continually attempts to register the default gateway MAC address. When the primary default gateway fails, the backup default gateway will be able to successfully register the default gateway MAC address and take over the responsibilities of the primary default gateway and become the active default gateway.