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