Because {HEAD ~ the dedicated modules} can be added to or taken out {TAIL ~ the switch architecture} based on the network environment, the switch is scalable and adaptable 
added to
Because { HEAD ~ the dedicated modules } can be added to or taken out { TAIL ~ the switch architecture } based on the network environment , the switch is scalable and adaptable
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL REL OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH