Optionally, but not necessarily, {HEAD ~ the direct file system access engine} is {TAIL ~ one or more Windows DFA kernel driver} 
Optionally , but not necessarily , { HEAD ~ the direct file system access engine } is { TAIL ~ one or more Windows DFA kernel driver }
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL