Which two actions, when applied in the LAN network segment, will facilitate Layer 3 CAPWAP discovery for lightweight AP? (Choose two.)

Question

Options

• AUtilize DHCP option 17.
• BConfigure WLC IP address on LAN switch.
• CUtilize DHCP option 43.
• DConfigure an ip helper-address on the router interface
• EEnable port security on the switch port

• A
  4% (1)
• B
  13% (3)
• C
  79% (19)
• E
  4% (1)

Explanation

CAPWAP Layer 3 Discovery Explanation

DHCP Option 43 (C) allows the DHCP server to embed the WLC's IP address directly in the DHCP response sent to the AP, enabling the AP to discover its controller even across different subnets. IP Helper-Address (D) is essential because it forwards broadcast DHCP requests from APs (which don't yet have an IP) across router boundaries to a centralized DHCP server, enabling Layer 3 reachability between the AP and WLC.

Why the distractors are wrong:

• Option A (DHCP Option 17) is used for TFTP server addresses, not WLC discovery - this is a common "close but wrong" trap.
• Option B (WLC IP on LAN switch) is not a valid configuration concept; WLC discovery is handled through DHCP/DNS, not switch configuration tables.
• Option E (Port security) is a security feature that restricts MAC addresses on a port - it has no role in controller discovery and would actually hinder AP connectivity.

Memory Tip: Think "43 Finds the Controller, Helper Crosses the Router" - Option 43 embeds the WLC address in DHCP, while the helper-address carries that DHCP message across Layer 3 boundaries. These two work as a team for cross-subnet AP discovery.

No community discussion yet for this question.