Chapter 6 Deploying Wireless Networks : Reference : FortiAP web-based manager : System Information : WTP Configuration
  
WTP Configuration
AC Discovery Type settings affect how the FortiAP unit discovers a FortiGate WiFi controller. By default, this is set to Auto which causes the FortiAP unit to cycle through all of the discovery methods until successful. For more information see “Controller discovery methods”.
AC Discovery Type
Static, DHCP, DNS, Broadcast, Multicast, Auto
AC Control Port
Default port is 5246.
AC IP Address 1
AC IP Address 2
AC IP Address 3
You enter up to three WiFi controller IP addresses for static discovery. Routing must be properly configured in both directions.
AC Host Name 1
AC Host Name 2
AC Host Name 3
As an alternetive to AC IP addresses, you can enter their fully qualified domain names (FQDNs).
AC Discovery Multicast Address
224.0.1.140
AC Discovery DHCP Option Code
When using DHCP discovery, you can configure the DHCP server to provide the controller address. By default the FortiAP unit expects this in option 138.
AC Data Channel Security by default accepts either DTLS-encrypted or clear text data communication with the WiFi controller. You can change this setting to require encryption or to use clear text only.