Reverse ARP (RARP)

This protocol is intimately related to the last one, given that it solves the
opposite problem: a machine knows its physical address but not its IP
address [9]. This happens, for example, in machines without a massive storage
capacity, which need to use a File Transfer Protocol (FTP) type protocol
over TCP/IP to load their set up program from a file server.
The function is very similar to ARP. The machine generates an RARP
request message in broadcast mode, providing its physical address. Another
machine, called the server, contains a table in its massive storage system with
the assignation of addresses, and it replies with an RARP-reply type message.
Note that this procedure will not be needed again until the machine is
reinitialized.