In another embodiment, {HEAD ~ a protection system} is provided for protecting {TAIL ~ data} of variable protection levels 
is provided for protecting
In another embodiment , { HEAD ~ a protection system } is provided for protecting { TAIL ~ data } of variable protection levels
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH