CNAM, which stands for Caller Name Delivery, is a technology that allows phone numbers to be linked to other alphanumeric data that displays on caller ID systems. CNAM names allow the use of 15 alphanumeric characters, always uppercase, and no use of punctuation beyond spaces. In the U.S., phone carriers issuing telephone numbers to businesses have the ability to feed in CNAM details that link to each number. Phone carriers share CNAM details with various CNAM database providers. When calls are made, the decision is up to the terminating carrier to perform a CNAM lookup on the incoming number using the databases operated by the CNAM database providers. The carrier displays the CNAM information on the end-user’s caller ID system when a call is coming in.
Trestle’s Smart CNAM API provides a similar caller name, however, without some of the limitations seen with the legacy CNAM technology. A sample response for Smart CNAM API is here:
{
"id": "Phone.3dbb6fef-a2df-4b08-cfe3-bc7128b6f",
"is_valid": true,
"phone_number": "+12069735100",
"belongs_to": {
"id": "Person.fffdcf06-0929-4b5a-9921-ee49b101ca84",
"name": "Waidong Lewis Syrws",
"firstname": "Waidong",
"middlename": "Lewis",
"lastname": "Syrws"
}
}The table below summarizes some of the differences between legacy CNAM and Smart CNAM API:
| Feature | CNAM | Smart CNAM API |
| Coverage | 50% | 90% |
| Business/Person Classification | No | Yes |
| Parsed Names | No | Yes |
| Junk Data (‘Wireless Caller’, etc.) | Yes | No |