When this object is set to 'true', the Gateway will check the
upstream TPDU destination address against the range of
IP addresses reserved for PLMN devices. If there is a
match, the TPDU is dropped. This check would enable
the Gateway to protect the GPRS network from some hacker
who may try to flood the Gateway and PLMN nodes with
intense data traffic.
When the object is set to 'false', the Gateway will not
perform any checking on the upstream TPDU for the
destination address.