# Inward Dialing Modification

## Purpose

The Inward Dialing Modification feature allows you to alter dial strings contained in inbound SIP and E1 ISDN calls. After adding substitution rules, you can apply them to both "Called Party" and "Calling Party" SIP/ISDN headers.

To program an Inward Dialing Modification rule, select an index number and program it with match criteria and the digits you wish to substitute.

To associate the rule with a SIP link, select the appropriate index number on the SIP Peer Profile Called Party Inward Dialing Modification or Calling Party Inward Dialing Modification form. To associate the rule with a device, select the appropriate index number on the SIP Device Capabilities.

To associate the rule with a E1 ISDN link, use the ISDN Called Party Inward Dialing Modification and ISDN Calling Party Inward Dialing Modification forms.

NOTES

- When you associate a rule with a link, you can select whether it applies to "called party" or "calling party" type SIP/ISDN headers. Called party SIP headers include Request URI, To, and Refer-To headers in Invite messages, and Contact headers in 3xx messages. Calling party SIP headers include From, P-Asserted-Identity, Referred-By, Diversion, and History-Info.

- When you associate a rule with a SIP device, the rule can only be applied to "called party" type SIP headers.

Use this form when performing the following tasks:

- Program SIP Trunks

- Program Embedded PRI/QSIG Trunks

## Rule Examples

A) In this example, "00" is added to incoming calls with dial strings that are 12 digits or longer:

1. Open the Inward Dialing Modification form.

2. Program the digit match settings:

3. For the Digits to Match, enter "x."

4. For the Digit Length Operator, select "greater than or equal to."

5. For the Digit length, enter "12."

3. Program the digit replacement settings:

- For the Number of Digits to Absorb, enter "0."

- For the Digits to be Inserted, enter "00."

4. Save the rule.

5. Associate the rule with a link or device.

B) In this example, "91" is added to incoming calls with dial strings that are 10 digits long:

1. Open the Inward Dialing Modification form.

2. Program the digit match settings:

3. For the Digits to Match, enter "x."

4. For the Digit Length Operator, select "equal to."

5. For the Digit length, enter "10."

3. Program the digit replacement settings:

- For the Number of Digits to Absorb, enter "0."

- For the Digits to be Inserted, enter "91."

4. Save the rule.

5. Associate the rule with a link or device.

## Conditions

- SIP dial strings must be from 1 to 32 digits in length.

## Field Descriptions

Parameter | Description | Default Value
Index | System-generated, protected field. Each index number represents a unique inward dialing modification rule. You can configure up to 100 rules. The rules are applied in consecutive order based on their index number. Rule #1 is applied before rule #2. |
Digits to Match | Enter the digits to match at the beginning of the dial string in inbound calls. Valid digits are 0-9, *, and #. Enter "x" as a wild card to match any valid incoming digit (0-9, *, or #). The maximum number of characters in this field is 32. The programmed digits match the initial digits of the dial string. This means that if you enter 613 in this field, the system will attempt to match 613 in the first three digits of the dial string. NOTE: This field must be programmed to create a valid rule. | Blank
Digit Length Operator | Select a digit length operator to apply to the match operation for inbound calls. Valid operators: - undefined - equal to - less than - greater than - greater than or equal to - less than or equal to This field works in conjunction with the "Digit Length" field. For example, if you select "equal to," the system matches the exact number of digits specified in the "Digit Length" field. NOTE: This field must be programmed with a value other than "undefined" in order to create a valid inward dialing modification rule. | undefined
Digit Length | Enter the number of digits to match (0-32) of the dial string in inbound calls. This field works in conjunction with the "Digit Length Operator" field. For example, if you enter "10" in this field and "equal to" in the Digit Length Operator field, the system matches dial strings that are 10 digits in length. It does not match dial strings that are longer or shorter. | 0
Number of Digits to Absorb | Enter the number of digits to absorb (0-32) at the beginning of the dial string in inbound calls. | 0
Digits to be Inserted | Enter the digits to insert at the beginning of the dial string in inbound calls. Valid digits are 0-9, *, and #. Leave this field blank to insert no digits. The maximum number of characters in this field is 32. | Blank