About proxy ARP
Proxy ARP enables a device on one network to answer ARP requests for an IP address on another network. With proxy ARP, hosts on different broadcast domains can communicate with each other as they would on the same broadcast domain.
Proxy ARP includes common proxy ARP and local proxy ARP.
Common proxy ARP—Allows communication between hosts that connect to different Layer 3 interfaces and reside in different broadcast domains.
Local proxy ARP—Allows communication between hosts that connect to the same Layer 3 interface and reside in different broadcast domains.