Have just turned up VNR between an Option 81C and a CS1000 via non-pri T1's. Internal calls to vacant numbers complete both directions. Also able to complete network calls to vacant numbers in the 81C to the CS1000. (These network trunks are also tielines.) Can't complete a DID call to a vacant number through the 81. I don't think I have a NCOS/FRL/TARG issue. Is the DITI YES (DID to TIELINE Allowed) prompt in the CDB NET_DATA mandatory for this scenario to work or can it still be a NARS related problem? I don't have option 131 in the 81C so I don't even get the DITI prompt.