Cisco IOS Digit Manipulation
Need to control the digits contained in the telephone number that enter or leave a gateway? Digit manipulation involves adding, subtracting, and changing telephone numbers. You can manipulate calling numbers, called numbers, and redirecting numbers, as well as the numbering plan and ISDN number type. Learn about the techniques that are applied to incoming or outgoing calls, or globally to all calls. You can also manipulate telephone numbers before or after a dial peer is matched.