What facts are true regarding controllers and APs in a Split MAC architecture?

The fact that is true regarding controllers and APs in a Split MAC architecture is that an IP tunnel is established between the AP and controller for AP management and control functions. A Split MAC architecture is a WLAN architecture where some of the MAC layer functions are performed by the APs (such as encryption, decryption, and frame acknowledgement) and some are performed by the controllers (such as authentication, association, roaming, and QoS). To communicate with each other, the APs and controllers establish an IP tunnel that carries the management and control frames between them. The IP tunnel can use protocols such as Lightweight Access Point Protocol (LWAPP) or Control And Provisioning of Wireless Access Points (CAPWAP). References: [CWNP Certified Wireless Network Administrator Official Study Guide: ExamCWNA-109], page 372; [CWNA: Certified Wireless Network Administrator Official Study Guide: ExamCWNA-109], page 362.