Question: how arp and rarp works?
Answer: In Address Resolution Protocol (ARP), Receiver's MAC address is fetched. Through ARP, (32-bit) IP address mapped into (48-bit) MAC address. Whereas, In Reverse Address Resolution Protocol (RARP), IP address is fetched through server. Through RARP, (48-bit) MAC address of 48 bits mapped into (32-bit) IP address.