The controller can also use a random selection algorithm in which {HEAD ~ the controller} selects {TAIL ~ an access code} at random from those stored in a memory list 
The controller can also use a random selection algorithm in which { HEAD ~ the controller } selects { TAIL ~ an access code } at random from those stored in a memory list
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH