Static Frame Relay addressing: If Inverse ARP is not operational, which command must be configured to ensure Layer 3 connectivity over Frame Relay?

Introduction / Context:
Inverse ARP dynamically discovers Layer 3 next-hop addresses from Frame Relay DLCIs. When it fails or is disabled (e.g., point-to-point subinterfaces, security policies), you must configure static mappings to maintain connectivity.

Given Data / Assumptions:

• Frame Relay network with known DLCIs.
• Inverse ARP is not functioning.
• Goal: Bind Layer 3 addresses to DLCIs manually.

Concept / Approach:
The 'frame-relay map' command statically maps a Layer 3 protocol and address (e.g., IP 10.1.1.2) to a DLCI and can specify broadcast capability. LMI type selection (ansi, cisco, q933a) affects signaling, not address resolution. There is no 'frame-relay arp' command for this purpose.

Step-by-Step Solution:

Verification / Alternative check:
After configuring a static map, 'show frame-relay map' should display the IP–DLCI association as static; routing adjacency (if any) should form successfully.

Why Other Options Are Wrong:
frame-relay arp: Not a valid method for static IP-to-DLCI mappings.
frame-relay interface-dci: Invalid syntax (likely typo for 'dlci').
frame-relay lmi-type: Sets LMI signaling type; does not create Layer 3 mappings.

Common Pitfalls:
Forgetting the 'broadcast' keyword, which is necessary for multicast/broadcast packets (e.g., routing protocols) to traverse the PVC.

Final Answer:
frame-relay map