The application means selects the desired packet data network identifiers based on {HEAD ~ services} requested by {TAIL ~ applications} 
The application means selects the desired packet data network identifiers based on { HEAD ~ services } requested by { TAIL ~ applications }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL