A data dependent scrambler communicates with the buffer, searches for a first m bit symbol that is non zero and is at least one of different than the plurality of m bit symbols in {HEAD ~ the user data} and different than inverses of the plurality of m bit symbols in {TAIL ~ the user data} 
A data dependent scrambler communicates with the buffer , searches for a first m bit symbol that is non zero and is at least one of different than the plurality of m bit symbols in { HEAD ~ the user data } and different than inverses of the plurality of m bit symbols in { TAIL ~ the user data }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL