{HEAD ~ The descriptors} can also be used for managing {TAIL ~ scrambling and descrambling control words}  
used for managing
{ HEAD ~ The descriptors } can also be used for managing { TAIL ~ scrambling and descrambling control words }
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH