The programmable device is programmed to include {TAIL ~ four processing engines}, each of which performs {HEAD ~ a single MD5 stage} having four MD5 operations performed by the MD5 stage 
The programmable device is programmed to include { TAIL ~ four processing engines } , each of which performs { HEAD ~ a single MD5 stage } having four MD5 operations performed by the MD5 stage
OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH