You using DN based?
Calling Party Number (CPN) Substitution
Description
CPN (Calling Party Number) substitution is typically used to show the customer's corporate name and number for all outgoing calls to the public network. The 3300 ICP provides two types of CPN substitution: DID-based and DN-based.
DID-based substitution is used for individual DID numbers or ranges of DID numbers and applies to calls over embedded PRI/DPNSS trunks, embedded BRI trunks ("T" interface only), and SIP trunks.
DN-based substitution is done at the directory number level and applies to calls over embedded PRI/DPNSS trunks and SIP trunks.
You can program both types of substitution on the same system, or within a cluster or network, with priority given to DN-based substitution.
What do you have programmed in the SIP peer profile?
Calling Line ID
Default CPN
Enter the default CPN up to 26 alphanumeric characters (a-z, A-Z and 0-9). This alphanumeric string is used in outgoing calls to replace the calling party number and on incoming calls to replace the called party number when a match is not found in the URI/Number Translation Form or the Outgoing DID ranges on the SIP Peer Profile Form.
Normally on outgoing calls (unless restricted or private) the default CPN would appear in the From header if a match is not found elsewhere.
If the "Use P-Asserted-Identity Header" option is set, the P-Asserted-Identity will be included and it will contain the Default CPN if a match is not found elsewhere. A "Privacy: id" header will also be included if the CPN is restricted or the number is marked private.
If the "Use P-Preferred-Identity Header" option is set and the "Use P-Asserted-Identity Header" is not set, the P-Preferred-Identity will be included and will contain the Default CPN.
For incoming calls, the ringing or answering party's number is replaced with the default CPN when a match is not found in the URI/Number Translation Form or the Outgoing DID ranges. This number will only be included in the P-Asserted-Identity header if the option is enabled.
To substitute specific numbers to DIDs, you may add numbers into the DID Ranges for CPN Substitution form and then select the appropriate numbers in the Outgoing DID Ranges panel located at the bottom of this form (SIP Peer Profile).
Note: Public numbers may be substituted by the Default CPN unless the option "Public Calling Party Number Passthrough" is set.
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