A Wireless LAN Controller (WLC)

So do you have a few independent WAPs or are you trying to cover a wide area with an array of WAPs? If it is the latter you will need a WLC

A WLC will use one of 2 protocols:

LWAPP: Light Weight Access Point Protocol or

CAPWAP: Control and Provisioning of Wireless Access Points

WAP's Come in 4 flavors:

Access Point Based (no WLC)

Cloud Based (Cloud WLC) (Meraki)

Virtual Controller Based (virtual WLC)

Physical Controller Based (physical WLC)