When an access point is seeking to join wireless LAN controller, which message is sent to the AP-Manager interface?

A Discovery Response is sent *by* the WLC *to* the AP after receiving a Discovery Request, not sent by the AP to join.

A DHCP Request is part of the IP address acquisition process for the AP, which typically happens before CAPWAP discovery, and is sent to a DHCP server, not specifically the WLC's AP-Manager interface for joining.

A DHCP Discover is also part of the IP address acquisition process for the AP, sent to a DHCP server, and precedes the CAPWAP discovery messages for joining the WLC.

When a lightweight access point (LAP) powers on and needs to join a Wireless LAN Controller (WLC), it first attempts to discover a WLC by sending a CAPWAP (Control and Provisioning of Wireless Access Points) Discovery Request message, which is directed towards the WLC's AP-Manager interface.