> ## Documentation Index
> Fetch the complete documentation index at: https://vida.io/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Phone Numbers and Channel Routing

> Choose and verify the phone, SMS, SIP, web, and forwarding routes that connect customers to a Vida Agent.

An Agent configuration defines behavior. Channel routing determines how a real customer reaches
that Agent. Treat routing changes as production changes: identify the current path, change one
thing, and test both directions afterward.

## Choose a calling route

| Need                                   | Recommended path                                                                    |
| -------------------------------------- | ----------------------------------------------------------------------------------- |
| A new managed number                   | Search for and assign a Vida phone number.                                          |
| Keep a number with its current carrier | Configure a supported bring-your-own number or forwarding path.                     |
| Move the number to Vida                | Follow the number-porting process.                                                  |
| Connect a PBX or carrier               | Use SIP registration, inbound SIP controls, or outbound SIP routing as appropriate. |
| Voice or chat from a website           | Publish an Agent profile or use the website embed.                                  |

See [Forward calls](/docs/sharing/forward), [Port an existing number](/docs/sharing/port-number), and the
[SIP guides](/docs/sip/sip-registration).

## Assign and verify a number

Confirm the exact Agent before purchasing, assigning, returning, or moving a number. After a change:

1. place an inbound call from an external phone
2. place an authorized outbound test
3. verify caller identity and the destination
4. inspect the resulting logs and conversation
5. test transfer and fallback behavior when the workflow uses them

Returning or disconnecting a number stops its current routing.

## Enable SMS deliberately

US application-to-person messaging requires business and use-case registration. Complete the
required registration, consent, and opt-out setup before sending production messages. Voice routing
working on a number does not mean outbound SMS is approved.

See [Enabling SMS](/docs/agents/enable-sms).

## Choose the correct SIP capability

* **SIP registration** gives the Agent credentials and an address of record for a supported PBX or
  carrier.
* **Inbound SIP access** controls which source systems may send calls to Vida.
* **Outbound SIP routing** tells Vida where matching outbound destinations should be sent.

Some deployments need more than one of these. Preserve unrelated allowlist entries and routes when
making a change.

## Keep a rollback path

Record the previous carrier, number destination, SIP route, and forwarding behavior before a
cutover. During launch, change one traffic source at a time and keep the old route recoverable until
representative calls succeed.

<Note>
  Configuring channels through the API? See
  [Phone numbers and SIP](/docs/api-reference/agent-guides/telephony).
</Note>