For example, {TAIL ~ a mechanism} is provided to enable {HEAD ~ access points} to perform automatic channel selection 
For example , { TAIL ~ a mechanism } is provided to enable { HEAD ~ access points } to perform automatic channel selection
OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH