Command:

isdn caller


Mode:

Router(config-if)#


Syntax:

isdn caller phone-number [callback] [exact]

no isdn caller phone-number [callback] [exact]

 

Syntax Description:

phone-number Remote telephone number for which to screen. Use the letter X to represent a single "don't care" digit. The maximum length of each number is 25 digits.
callback (Optional) Enables callback.
exact (Optional) Performs matching on incoming telephone number exactly as entered.

 

Command Description:

To configure ISDN caller ID screening and optionally to enable ISDN caller ID callback for legacy dial-on-demand routing (DDR), use the isdn caller command in interface configuration mode. To disable this feature, use the no form of this command.

This command configures the router to accept calls from the specified number.

When the optional callback keyword is used and a call is received from one of the callback numbers, the initial call is rejected (hence, not subject to tolls) and a callback is initiated to that calling number.

When Xs are used in the callback number, dialer caller screening is based on a best match system that uses the number of Xs as a criterion. To make callback calls only to specified numbers or ranges of numbers but to accept any other incoming calls, make sure that the number of Xs in any configuration line that uses the callback keyword is less than the number of Xs in any configuration line that does not use the keyword.

For example, if you use at most four Xs in the configuration lines with the callback keyword, then to accept calls from other numbers use at least five Xs in a configuration line that does not use the keyword.

When a telephone number is entered without the exact keyword, the software compares each number going from right to left until matching numbers are detected. For example, if the phone-number argument is 4085551234, calls from telephone numbers 1234, 51234, 5551234, and 4085551234 would be accepted, but calls from telephone numbers 44 and 4155551234 would be rejected.

If you want to accept a telephone number exactly as it is configured, enter it with the exact keyword. For example, if the phone-number argument is 5551212 and the exact keyword is applied, only the telephone number 5551212 is accepted; calls from telephone numbers 408551212 and 51212 would be rejected.

The maximum length of each telephone number is 25 characters. There is no limit on the numbers you can specify per interface.


Example:

The following example configures the router to accept a call containing the numbers 415 555-1234:

Router(config-if)#isdn caller 4155551234

The following example configures the router to accept a call only from telephone number 555-1234:
Router(config-if)#isdn caller 5551234 exact
In the above example, a call from telephone number 415 555-1234 would be rejected.
The following example configures the router to accept a call with telephone number containing 415 555-12 and any numbers in the last two positions:
Router(config-if)#isdn caller 41555512xx
In the following example, callback calls will be made only to numbers in the 555 and 556 exchanges, but any other telephone number can call in:
Router(config-if)#isdn caller 408555xxxx callback Router(config-if)#isdn caller 408556xxxx callback Router(config-if)#isdn caller xxxxx


Misconceptions:

None.


Related Commands:

show dialer


© Cisco Systems, Inc. 2001, 2002
World Wide Education

Converted from CHM to HTML with chm2web Pro 2.85 (unicode)