What protocol is used on the Local Area Network (LAN) to obtain an IP address from it's known MAC address?

Question

Options

• AReverse address resolution protocol (RARP)
• BAddress resolution protocol (ARP)
• CData link layer
• DNetwork address translation (NAT)

• A
  86% (24)
• B
  4% (1)
• C
  4% (1)
• D
  7% (2)

Explanation

RARP (Reverse Address Resolution Protocol) is correct because it works in the reverse direction of standard ARP - given a known MAC address, it queries a RARP server on the LAN to retrieve the corresponding IP address. This was commonly used by diskless workstations that knew their hardware address but needed to discover their IP at boot time.

Why the distractors are wrong:

• B (ARP) does the opposite - it resolves a MAC address from a known IP address, not the other way around.
• C (Data Link Layer) is an OSI model layer, not a protocol; it describes where addressing happens, not how resolution is performed.
• D (NAT) translates private IP addresses to public IP addresses for routing across networks - it has nothing to do with MAC-to-IP resolution.

Memory tip: Think of the "R" in RARP as "Reverse" - ARP finds MAC from IP, so RARP finds IP from MAC. If you can remember ARP's direction, just flip it for RARP.

No community discussion yet for this question.