Licson Lee says to YSITD
Proxy ARP is a technique by which a proxy device on a given network answers the ARP queries for an IP address that is not on that network. The proxy is aware of the location of the traffic's destination, and offers its own MAC address as the (ostensibly final) destination.[1] The traffic directed to the proxy address is then typically routed by the proxy to the intended destination via another interface or via a tunnel. 這是 Proxy ARP 的定義