Consider the following two statements: S1: Destination MAC address of an ARP reply is a broadcast address. S2: Destination MAC address of an ARP request is a broadcast address. Which one of the following choices is correct? A. Both S1 and S2 are true B. S1 is true and S2 is false C. S1 is false and S2 is true D. Both S1 and S2 are false

GATE 2021 · Computer Networks · Network Protocols · medium

Answer: S1 is false and S2 is true — Option C

1. Evaluate S1 — ARP Reply destination: When Host B sends an ARP Reply, it already knows Host A's MAC address (from the ARP Request it received). Therefore, the ARP Reply is sent as a unicast frame directly to Host A's MAC address — NOT broadcast. S1 is FALSE.
2. Evaluate S2 — ARP Request destination: When Host A sends an ARP Request, it does NOT know the MAC address of the target. Therefore, the ARP Request must be sent to the broadcast MAC address FF:FF:FF:FF:FF:FF so every device on the local network segment receives it and the target can respond. S2 is TRUE.