CLID Rewrite

CLID Rewrites allows you to adjust the Caller ID to be displayed just before it is sent to the SIP provider.

Many SIP providers require Caller ID's number to be in a specific format for it to be accepted. Rewrites allows you to modify any Caller ID number to conform to the SIP providers requirements.

Trunk Groups also provide a more sophisticated version of CLID Rewrites which allows you to get creative with what CLID you display. Trunk CLID Rewrites (the ones on this page) are only for formatting a CLID correctly for a SIP Provider.

The requirement to have both Trunk and Trunk Group CLID Rewrites comes from the fact that a Trunk Group allows you to cluster multiple Trunks into a group. The problem is that each Trunk may be via a different provider and each may have their own CLID formatting requirements. The Trunk CLID Rewrite lets you ensure that each SIP Provider is passed the correct format regardless of the what format the more creative Trunk Group has set.

Rewrites

A Rewrite consists of a:

Pattern which is used to match numbers dialed
Strip prefix length which optionally removes digits from the start of the Caller ID.
Replacement prefx which optionally adds new digits to the start of the Caller ID.

Example (1)

The area code for local numbers is 03

User CLID is local number: 8320 8100

SIP provider requires the full area code on any CLID presented:

Pattern Match On: Caller ID

Pattern: XXXX XXX

Strip prefix Length: 0

Replacment prefix: 03

The pattern matches 8320 8100 and adds an 03 prefix to give 03 8320 8100

Example (2)

The area code for local numbers is 03

User's CLID is national number: 02 8320 8100

SIP provider requires the full international code on any CLID presented:

Pattern Match On: Caller ID

Pattern:XX XXXX XXX

Strip prefix Length: 1

Replacment prefix: 612

The pattern matches 02 8320 8100, strips the leading '0' to give 2 8320 8100 and then adds an prefix of 612 to give 612 8320 8100

Patterns

The order of patterns is important. When looking for a pattern that matches a phone number the system starts from the top pattern and evaluates each pattern in order until a match is found. That pattern is applied and any further patterns are ignored.

If a CLID does not match any Rewrite Pattern then it is passed unchanged.

Fields

Field	Description
Name	A name for the pattern that will be meaningful to you.
Description	A description of what the pattern is used for.
Pattern	The Pattern that CLID's will be matched against. If it matches then the Rewrite will be applied
Strip Prefix Length	The number of digits to strip of the start of the CLID.
Replacement prefix	The digits to add to the start of the CLID after the strip prefix has been done.
Test Phone No.	This is a convenience field that allows you to enter a CLID (phone number) that you expect to match the Pattern. Enter a CLID and then click the Test button. The results will be displayed in the Results field.
Results	Displays the results of the test.