Is HSRP a proprietary protocol developed by Cisco?

HSRP, or Hot Standby Router Protocol, is indeed a proprietary protocol developed by Cisco. It is designed to provide high availability and redundancy for network gateways, allowing for seamless failover in the case of a router or gateway failure. HSRP enables multiple routers to work together to present the illusion of a single virtual router to the hosts on the network. One of the core functionalities of HSRP is that it allows one router to take over the responsibilities of another router if it becomes unavailable, thus ensuring continuous network services.

The proprietary nature of HSRP means that it is specifically designed for use in Cisco environments and is not universally supported by other vendors, distinguishing it from some other standards-based protocols. This unique aspect enhances its efficacy within Cisco environments, where network engineers can optimize their configurations to take full advantage of HSRP's capabilities.

In contrast, other options imply varying degrees of universality, applicability, or version specificity, which do not align with HSRP's established status as a Cisco-only solution.