The system includes communications electronics adapted to provide radio communication with {HEAD ~ remote communications units}, which are capable of maintaining {TAIL ~ an independent ledger} of transaction history 
are capable of maintaining
The system includes communications electronics adapted to provide radio communication with { HEAD ~ remote communications units } , which are capable of maintaining { TAIL ~ an independent ledger } of transaction history
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH