Cisco's Hot Standby Routing Protocol (HSRP), which provides automatic router backup when you configure it on Cisco routers that run the Internet Protocol (IP) over Ethernet, Fiber Distributed Data Interface (FDDI), and Token Ring local-area networks (LANs). HSRP is compatible with Novell's Internetwork Packet Exchange (IPX), AppleTalk, and Banyan VINES, and it is compatible with DECnet and Xerox Network Systems (XNS) in certain configurations.

The Virtual Router Redundancy Protocol (VRRP) eliminates the single point of failure inherent in the static default routed environment. VRRP specifies an election protocol that dynamically assigns responsibility for a virtual router (a VPN 3000 Series Concentrator cluster) to one of the VPN Concentrators on a LAN. The VRRP VPN Concentrator that controls the IP address(es) associated with a virtual router is called the Master, and forwards packets sent to those IP addresses. When the Master becomes unavailable, a backup VPN Concentrator takes the place of the Master.