Cisco Certified Network Associate (CCNA) Practice Exam 2026 - Free CCNA Practice Questions and Study Guide

The Inverse Address Resolution Protocol (IARP) is specifically designed to help network devices discover the IP address associated with a Data Link Connection Identifier (DLCI) or Virtual Circuit (VC) in Frame Relay networks. It operates by allowing a device to send a request to the network to find out what IP address corresponds to a given DLCI. This is particularly useful because Frame Relay operates at the data link layer, and devices need to map these identifiers to their corresponding network layer addresses for proper communication.

In contrast, the other options serve different functions in networking. Address Resolution Protocol (ARP) is used to map IP addresses to MAC addresses in Ethernet networks, not for discovering information about DLCIs. Network Address Translation (NAT) is used to translate private IP addresses to public IP addresses and does not involve DLCIs. Dynamic Host Configuration Protocol (DHCP) is used for dynamically assigning IP addresses to hosts on a network, but it does not relate to the discovery of IP addresses based on DLCIs or VCs. Thus, IARP is the appropriate protocol for this specific purpose.