Separately using the URN the ALR contacts {HEAD ~ the HLR} to make a validity check 117 of {TAIL ~ the URL} 
Separately using the URN the ALR contacts { HEAD ~ the HLR } to make a validity check 117 of { TAIL ~ the URL }
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL