What are the elements for Device Mobility configuration?

Device Mobility relies on a physical location to identify the subnet(s) where a roaming device is connected, a device pool that contains the locale and region settings to apply when the device is at that location, and a Device Mobility group that ties the device pool to its associated physical location - together these three elements determine what settings a roaming device receives based on its current network location.

Region is a component within a device pool but is not itself a top-level Device Mobility configuration element; physical location is required instead of region as the direct element.

Region is not a standalone Device Mobility configuration element; the correct elements are physical location, device pool, and Device Mobility group.

A Cisco IP phone is the endpoint that uses Device Mobility, not a configuration element of the feature itself; physical location is the missing required element.