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