{HEAD ~ The first computer system} later receives {TAIL ~ an encrypted response} from the second computer system and processes the encrypted response to determine whether the second computer system is authorized to access the software 
receives
{ HEAD ~ The first computer system } later receives { TAIL ~ an encrypted response } from the second computer system and processes the encrypted response to determine whether the second computer system is authorized to access the software
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH