{TAIL ~ The access controller} 160 includes an interface 710, a DS0 Handler 720, a microprocessor unit 730, a message processor 740, and {HEAD ~ a clock processor} 750 
{ TAIL ~ The access controller } 160 includes an interface 710 , a DS0 Handler 720 , a microprocessor unit 730 , a message processor 740 , and { HEAD ~ a clock processor } 750
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH