This has the advantage that {TAIL ~ data} can be transferred simultaneously by packet switching and {HEAD ~ line switching} 
This has the advantage that { TAIL ~ data } can be transferred simultaneously by packet switching and { HEAD ~ line switching }
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD