Abstract: The present invention provides a method for determining an authorization for a call based on an Originating Station Number (OSN) in a Primary Rate Interface (PRI) in a virtual private network (VPN) customized dialing plan. A new access type is defined enabling first authorization levels to be assigned at the level of the OSN. A service logic database at a Service Control Point stores second authorization level required to complete the call. A combination of a Switch ID (SwID) of the Service Switch Point (SSP) through which the call is being made and the Trunk Group Number (TGN) of the Private Branch Exchange (PBX) along with the OSN or range of OSNs serves as a primary key to the database. The first authorization level is compared to the second authorization level required to proceed with a call, and an action is selected based on the results of the comparison.

Abstract: Method and system of call screening. The method and system including screening of calls according to call screening instructions. The call screening instructions may include instructions for performing any number of call screening operations, including instructions associated with allowing or blocking international telephone calls.

Abstract: A method and system for handling identical VPN numbers assigned to multiple companies using a nature of address/number identifier initiated as public. The method includes receiving a query from a switch module to determine routing information for a call initiated by a calling party, the query including dialed digits with a nature of address identifier, and a calling party identifier updating the nature of address identifier associated with dialed digits to a private type code if a VPN coding identifier is determined present, looking up routing information associated with the dialed digits in a look-up table corresponding to the calling party identifier if the nature of address identifier includes the private type code, and transmitting the routing information to the switch module.