What is the difference between HSRP and VRRP?

HSRP (Hot Standby Router Protocol) and VRRP (Virtual Router Redundancy Protocol) are both protocols used for providing redundancy and high availability in a network. The main difference between HSRP and VRRP is the vendor support and the way they handle the election of the active router.

HSRP is a Cisco proprietary protocol, while VRRP is an industry standard protocol supported by multiple vendors. This means that HSRP is typically used in Cisco environments, while VRRP can be used in a multi-vendor network.

In terms of the election process, HSRP uses a priority value to determine the active router. The router with the highest priority becomes the active router, and if there is a tie, the router with the highest IP address is elected. On the other hand, VRRP uses a priority value as well, but it also includes a concept of a virtual router ID. The router with the highest priority and virtual router ID becomes the active router.

Another difference is the number of routers that can participate in the redundancy group. HSRP supports up to 255 routers, while VRRP supports up to 255 routers as well, but some implementations may have limitations.

Overall, both HSRP and VRRP serve the same purpose of providing redundancy and high availability, but they differ in terms of vendor support, election process, and the number of routers supported.