What protocol does the router or host use to find a MAC address for a destination IP address when it determines that the IP address is on the local network?

The Address Resolution Protocol (ARP) is employed by the host or router when a destination IP address is determined to be local on one of its interfaces. The Internet Group Management Protocol (IGMP) is used to build multicast sessions for switches and routers. Reverse Address Resolution Protocol (RARP) is used to obtain an IP address assigned for a specific MAC address. RARP has been replaced with DHCP and is no longer used outside of networking theory. The Internet Control Message Protocol (ICMP) is used with connectivity tools such as ping and tracert. ICMP is also used to notify a sender when the destination network is unreachable.