It is further contemplated that {TAIL ~ portable devices} may communicate with {HEAD ~ one or more central computers} via wired or wireless communication links 
It is further contemplated that { TAIL ~ portable devices } may communicate with { HEAD ~ one or more central computers } via wired or wireless communication links
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH