A mobility group is a collection of WLC that acts as a virtual WLC.
All (different) WLC’s must have directly contact with other WLCs.
Up to 24 WLC and 3600 AP’s are supported per mobility group.
A mobility group requires the all the WLCs uses the same virtual IP address
All the WLCs must use the same mobility domain name.
Allowing single WLAN to be supported across mulitple dynamic interfaces (VLANs)
AP Groups do not allow mulitcast roaming across group boundaries.
RF Groups also known as RF Domains is a cluster of WLCs that collectively coordiante and calulate their RRM (Radio Resource Management)