Which option is the first in the AP's dynamic discovery sequence to find the Master Controller?

The first step in the dynamic discovery sequence for an Access Point (AP) to find the Master Controller is through ADP Multicast. When an AP boots up, it initially attempts to discover its Master Controller by sending out an ADP (Aruba Discovery Protocol) multicast to locate other devices in the network. The AP will broadcast a packet to a specific multicast address that is known to be used by the Master Controller. This allows it to find the controller without needing prior configuration information.

This method is crucial because it is the most immediate way for the AP to seek out the Master Controller on the network, enabling a quick and automated discovery process as the AP comes online. Other mechanisms, such as DHCP options or DNS queries, come into play later in the discovery sequence, but they rely on the network's configurations to provide necessary details like IP addresses, making them secondary to the initial multicast method employed by ADP.