The embodiments of the invention include a network element implementing {HEAD ~ an optical line terminal} that is configured to improve {TAIL ~ efficiency} in a passive optical network  
is configured to improve
The embodiments of the invention include a network element implementing { HEAD ~ an optical line terminal } that is configured to improve { TAIL ~ efficiency } in a passive optical network
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH