Preferably, {HEAD ~ the current transaction information} is used to update {TAIL ~ both the remote ledger} and the shadow ledger 
is used to update
Preferably , { HEAD ~ the current transaction information } is used to update { TAIL ~ both the remote ledger } and the shadow ledger
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH