The data transaction system uses a first stage for transferring the data unit from {HEAD ~ the upper layer} to {TAIL ~ the storage layer}, and a second stage to save the transferred data unit independent of the upper layer 
to
The data transaction system uses a first stage for transferring the data unit from { HEAD ~ the upper layer } to { TAIL ~ the storage layer } , and a second stage to save the transferred data unit independent of the upper layer
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH