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