{HEAD ~ a data pattern enforcer} for applying {TAIL ~ said rules} to packets at the adaptor layer; and 
for applying
{ HEAD ~ a data pattern enforcer } for applying { TAIL ~ said rules } to packets at the adaptor layer ; and
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH