(InARP) Additions to
ARP typically
used for
Frame Relay.
Frame Relay stations
route frames 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
Ethernet
LAN, however RARP answers the question "What is my IP
Address?" whereas InARP answers the question "What is your
protocol address?".
See RFC 2390.