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

# SIP

> Receive calls with a voice agent, place outbound calls from your own numbers, and transfer calls to your human team

**Connection type:** Channel

Use your existing telephony provider, dialer, or PBX with SubVerse voice agents. A SIP trunk connects your phone numbers to SubVerse, so your agents can answer incoming calls and place outgoing calls on those same numbers.

## What you can do

| Capability | What it does |
| - | - |
| **Answer inbound calls** | Route calls from your numbers to SubVerse and pick the voice agent that handles them. |
| **Place outbound calls** | Let voice agents call customers from your numbers, using your provider's network and rates. |
| **Escalate to a human** | Transfer a live call to your agent queue or extension, with an optional call summary for context. |

## How it works

### Inbound

**Caller** → **Your SIP provider** → **SubVerse SIP server** → **Voice agent**

### Outbound

**Voice agent** → **SubVerse SIP server** → **Your SIP provider** → **Customer**

### Escalation

**Voice agent** → **SIP REFER** → **Your agent queue** → **Human agent**

Calls are secured with digest authentication (username and password). Your provider stays in control of numbers, routing, and billing.

## What you'll need

* A SIP trunk from any SIP-compliant provider, dialer, or PBX
* One or more phone numbers on that trunk, in international format
* A SIP username and password for the trunk
* Access to your firewall, to allow traffic from SubVerse
* A voice agent in SubVerse, to answer inbound calls
* A transfer destination (SIP URI or extension), if you plan to escalate calls

## Provider guides

<CardGroup cols={3}>
  <Card title="Twilio" icon="phone" href="/integrations/telephony-twilio">
    Configure a Twilio SIP trunk with SubVerse
  </Card>

  <Card title="Telnyx" icon="phone" href="/integrations/telephony-telnyx">
    Configure a Telnyx SIP trunk with SubVerse
  </Card>

  <Card title="Plivo" icon="phone" href="/integrations/telephony-plivo">
    Configure a Plivo SIP trunk with SubVerse
  </Card>
</CardGroup>

<Note>
  Step-by-step setup is in the SubVerse dashboard: go to **Integrations → SIP** and open the **Documentation** tab.
</Note>


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