{TAIL ~ The radio port} then transmits, over a pre established unidirectional virtual ciruit, {HEAD ~ the OA&M cell} to a radio port manager 
{ TAIL ~ The radio port } then transmits , over a pre established unidirectional virtual ciruit , { HEAD ~ the OA&M cell } to a radio port manager
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH