(InarP) Additions to arP typically used for Frame Relay. [Any other examples of its use?] Frame Relay stations routeframes of a higher level protocol between LANs, across a Permanent Virtual Circuit. These stations are identified by their {Data Link Control Identifier} (DLCI), equivalent to an {Ethernet address} in a LAN itself. InarP allows a station to determine a protocol address (e.g. IP address) from a DLCI. This is useful if a new {virtual circuit} becomes available. Signalling messages announce its DLCI, but without the corresponding protocol address it is unusable: no frames can be routed to it. Reverse arP (RarP) performs a similar task on an EthernetLAN, however RarP answers the question "What is my IP Address?" whereas InarP answers the question "What is your protocol address?". See RFC 2390. (2000-01-15)