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Technology

Hot Standby Router protocol (HSRP)

This is cisco proprietary protocol and communicates via UDP multicast to 224.0.0.2 at port 1985. It uses active and standby routers. The active router forwards the virtual mac address. The standby checks to make sure if the...

Technology

First Hop Reduncy Protocol

First Hop Redundancy protocols (FHRP) provide gateway redundancy to end hosts. When a host in a network boots up, it get a gateway IP using DHCP. If the gateway goes down, the host cannot reach devices outside of that network...