{TAIL ~ A communications channel} comprises a buffer that receives user data that includes a plurality of {HEAD ~ m bit symbols} 
{ TAIL ~ A communications channel } comprises a buffer that receives user data that includes a plurality of { HEAD ~ m bit symbols }
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD