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