develop a response message to be sent to the first computer over the communications link advising {HEAD ~ the first computer} of a successful or unsuccessful receipt of {TAIL ~ the communications packet}, and 
develop a response message to be sent to the first computer over the communications link advising { HEAD ~ the first computer } of a successful or unsuccessful receipt of { TAIL ~ the communications packet } , and
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH