{TAIL ~ The switching hub} transmits the received data only to designated ones among the connected devices, and transmits the received data to {HEAD ~ the repeater hub} 
{ TAIL ~ The switching hub } transmits the received data only to designated ones among the connected devices , and transmits the received data to { HEAD ~ the repeater hub }
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 HEAD HEAD HEAD HEAD HEAD HEAD HEAD