{TAIL ~ Operating means} are provided for operating the first service in {HEAD ~ connection} with the second service, so that the first service can utilize the second channel 
{ TAIL ~ Operating means } are provided for operating the first service in { HEAD ~ connection } with the second service , so that the first service can utilize the second channel
TAIL TAIL TAIL TAIL TAIL TAIL 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 OTH OTH