We can add call barring to the following types of calls. If you want to restrict calling on your lines Mandatory Account Codes might be the better option
• International-International, InterLATA International, and International toll free calls
• National and mobile-IntraLATA, InterLATA national, FGD cut through, FGB, Other N11, and Other Non-geographic calls
• Operator-Operator and Operator Service calls
• Access codes
• Access codes that change configuration-This value is typically used for a PBX. Because PBX lines are shared between users, you may want to prevent users from changing the configuration through the handset because this would affect other users of the PBX.
• Directory assistance