{TAIL ~ Scanning engine} 310 sends request 315 to direct {HEAD ~ file system access engine} 360 
{ TAIL ~ Scanning engine } 310 sends request 315 to direct { HEAD ~ file system access engine } 360
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH