a control unit that carries out {TAIL ~ connection} and disconnection to and from each of the host computers as {HEAD ~ sources} of print requests according to the host information registered in said registration unit 
a control unit that carries out { TAIL ~ connection } and disconnection to and from each of the host computers as { HEAD ~ sources } of print requests according to the host information registered in said registration unit
OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH