This read-write enumerated value determines the type of screening performed on the calling party number for calls entering the network at this port, choosing among options like node-prefix, port-prefix, node-prefix-or-port-prefix, address, node-prefix-or-address, port-prefix-or-address, and a further combined option, where the switch performs a bit-wise (prefix) or byte-wise (address) comparison against the configured prefix/address databases. This is the access-control mechanism that decides whether an incoming call's claimed calling-party number is validated against known prefixes, known full addresses, or some combination, rejecting or flagging calls that don't match an authorized pattern. An engineer locking down a port so only calls presenting a calling number matching a specific corporate address block are accepted would set svcConfigCgPtyScreenMode to node-prefix(1) or address(4) depending on whether the authorized range is expressed as a prefix or exact addresses.