In what scenario does a device respond with an ARP reply?

In what scenario does a device respond with an ARP reply?

• A. When it receives an ARP broadcast
• B. When it has never seen the IP address before
• C. When a packet is not successfully delivered
• D. When it is configured to ignore ARP requests

Answer: (A)

A device responds with an ARP reply when it receives an ARP broadcast because the ARP protocol is designed to resolve IP addresses into MAC addresses. In a typical scenario, when a device wants to communicate with another device on the same local network but only knows its IP address, it will send an ARP request as a broadcast to all devices on that network segment. This request asks, “Who has this IP address? Please send me your MAC address.” When the device that owns the specified IP address receives this broadcast ARP request, it recognizes that it needs to respond, thus sending back an ARP reply that includes its MAC address. This exchange allows the original sender to learn the MAC address associated with the IP address, enabling successful data transmission between the two devices. In contrast, situations where a device has never seen the IP address before or when the packet is not successfully delivered do not directly result in an ARP reply. Similarly, a device configured to ignore ARP requests would not send an ARP reply. The core function of ARP revolves specifically around the broadcast request and subsequent response mechanism.

A device responds with an ARP reply when it receives an ARP broadcast because the ARP protocol is designed to resolve IP addresses into MAC addresses. In a typical scenario, when a device wants to communicate with another device on the same local network but only knows its IP address, it will send an ARP request as a broadcast to all devices on that network segment. This request asks, “Who has this IP address? Please send me your MAC address.”

When the device that owns the specified IP address receives this broadcast ARP request, it recognizes that it needs to respond, thus sending back an ARP reply that includes its MAC address. This exchange allows the original sender to learn the MAC address associated with the IP address, enabling successful data transmission between the two devices.

In contrast, situations where a device has never seen the IP address before or when the packet is not successfully delivered do not directly result in an ARP reply. Similarly, a device configured to ignore ARP requests would not send an ARP reply. The core function of ARP revolves specifically around the broadcast request and subsequent response mechanism.