Each user process is operative to retrieve a requested title from two or more of {TAIL ~ the processors} via the backbone switch and to assemble a requested title for delivery to {HEAD ~ a requesting subscriber location} 
Each user process is operative to retrieve a requested title from two or more of { TAIL ~ the processors } via the backbone switch and to assemble a requested title for delivery to { HEAD ~ a requesting subscriber location }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD