2.2.4 TIF NS Handling of IAM Message

When an IAM message is received and successfully decoded, an Number Portability lookup is performed on the CdPN, the CgPN, or both.

For the CdPN, upon successful retrieval of the Called Party DN (Private), the CdPN is substituted in the outgoing IAM message.

For the CgPN, upon successful retrieval of the Calling Party DN (Public), the CgPN is substituted in the outgoing IAM message. If the Calling Party's Category is not the same as the value for the TIFOPTS nspublic configuration option and the lookup was successful, the Calling Party's Category is changed to the nspublic option value in the outgoing IAM message. The outgoing IAM message is then relayed.