ANI vs CNAM: what your carrier sends and shows

ANI is the phone number your call carries; CNAM is the name shown alongside it. The catch is that you send the number, but the receiving carrier looks up the name. They live in two different places, and confusing them is the most common caller-ID surprise in outbound dialing.

ANI: the number you send

ANI (Automatic Number Identification) is the originating number attached to your outbound call. In VICIdial it is the caller ID you set on the campaign or list, and your Carrier passes it along the Trunk as the ANI. It travels in the SIP (Session Initiation Protocol) signaling, usually in the From or P-Asserted-Identity header. You control it directly: change the campaign caller ID and you change the number every called party sees. Carriers expect this number in E.164 format on most routes.

CNAM: the name someone else looks up

CNAM (Caller ID Name) is the text label, like a business name, that appears under the number on the recipient's phone. Here is the part that trips people up: you do not send the name. The terminating carrier (the one serving the person you called) takes the ANI you sent and looks it up in a LIDB database, which is the shared store of caller-name records. Whatever name is registered against your number in LIDB is the CNAM (caller ID name) that shows. Your own carrier has no say in it on most calls.

Two paths, two owners

Following one call makes the split clear: the number goes out with the call, but the name is fetched on arrival by a different carrier.

flowchart LR
  A[VICIdial campaign caller ID] --> B[ANI in SIP From header]
  B --> C[Your carrier sends call]
  C --> D[Terminating carrier]
  D --> E[LIDB lookup on ANI]
  E --> F[CNAM name]
  D --> G[Recipient phone]
  F --> G
  B --> G

Why this matters for results

A few practical consequences fall out of the split:

• Not every recipient sees a name. Mobile carriers often skip the LIDB dip or use their own data, so the same call can show a name on a landline and just the number on a cell.
• Wrong or missing names hurt answer rates. If the LIDB record is stale, recipients see an unfamiliar name or nothing, and pick up less.
• Fixing CNAM is a number-ownership task, not a dialer setting. There is no VICIdial field for it; you update the LIDB record for the number.

Setting the ANI itself does happen in VICIdial, on the campaign or list caller ID. If you want to send different numbers from different lists, the same caller-ID controls apply; for how carrier IP authorization affects which numbers a carrier will accept from you, see register vs IP authentication.

Caller ID is one slice of carrier setup. For the whole picture, read our VICIdial carrier integration guide.

Bring your own carrier and numbers; we provision a dedicated VICIdial server for you in under 40 seconds. See our plans to start.