Inverse ARP Explained

D

Inverse ARP (Address Resolution Protocol) is used in Frame Relay networks to resolve the mapping between a Layer 3 (network layer) address, such as an IP address, to a Layer 2 (data link layer) address, such as a MAC address or DLCI (Data Link Connection Identifier).

The purpose of Inverse ARP is to allow a device on a Frame Relay network to discover the DLCI associated with a particular destination IP address, without requiring manual configuration of the mapping between IP and DLCI addresses. This is important because Frame Relay networks can have many connections and maintaining a manual mapping of IP to DLCI addresses can be difficult and time-consuming.

Therefore, the correct answer to this question is option D: to map a known DLCI to an IP address.

Option A is incorrect because it describes the function of ARP, not Inverse ARP. ARP maps a known IP address to a MAC address.

Option B and E are also incorrect because SPID (Service Profile Identifier) is not used in Frame Relay networks.

Option C and F are incorrect because they describe the function of ARP, not Inverse ARP, and they also map IP addresses to MAC addresses or DLCI addresses respectively.