Which interface IP address serves as the tunnel source for CAPWAP packets from the WLC...

The AP-manager interface is used by the WLC to communicate with access points using CAPWAP packets2. The AP-manager interface has an IP address that serves as the tunnel source for CAPWAP packets from the WLC to an AP3. The service interface is used for out-of-band management of the WLC, such as Telnet and SSH4. The trunk interface is used to connect the WLC to a switch and carry multiple VLANs5. The virtual AP connection is not an interface, but a logical connection between an AP and a WLC that allows multiple SSIDs to be supported by a single AP6.