Hot Standby Router Protocol. HSRP is a proprietary Cisco protocol that allows a group of redundant IP routers to function as a single virtual device. The protocol allows hosts to maintain connectivity even if the actual first-hop router they are using fails. HSRP can run on Cisco routers that run IP over Ethernet, FDDI, and Token Ring. It is also compatible with Novell, AppleTalk, and Banyan VINES networks.