> ## Documentation Index
> Fetch the complete documentation index at: https://docs.famulor.io/llms.txt
> Use this file to discover all available pages before exploring further.
# Vonage Integration
> Connect a Vonage phone number to Famulor via Elastic SIP Trunking
**Done for you — any region, any country (our EU partner carrier)**
If you prefer not to configure a SIP trunk or import numbers yourself, our **EU partner carrier** can supply **local numbers in any region and any country**, set up the **SIP trunk**, and **import the connection into Famulor** for you. Provisioning runs **end-to-end through the partner** (carrier-side), so you skip DIY trunk and number import in Famulor.
* **Custom number region / full-service onboarding:** [Famulor Custom Number Region form](https://tally.so/r/w4bN2Y)
* **More detail or bespoke options:** [support@famulor.de](mailto:support@famulor.de)
# Connect a Vonage Number to Famulor
This guide connects a **Vonage** phone number to Famulor via **Elastic SIP Trunking**.
Famulor has **no** dedicated Vonage import feature. You set up an **Elastic SIP Trunk** in Vonage and connect it through **Integrate SIP trunk** in Famulor.
The trunk has two directions:
* **Termination** (outbound calls): Vonage gives you a SIP domain + credentials that Famulor uses to send outbound calls.
* **Origination** (inbound calls): Vonage forwards calls to **Famulor's SIP address**.
## How it works
```mermaid theme={null} theme={null}
sequenceDiagram
participant C as Caller
participant V as Vonage
participant FA as Famulor
participant A as AI assistant
Note over V,FA: Inbound – origination to „Our SIP address"
C->>V: Call to your Vonage number
V->>FA: SIP call to „Our SIP address"
FA->>A: Call routed to assigned assistant
A->>FA: Voice response (real time)
FA->>C: Conversation with AI assistant
Note over FA,V: Outbound – termination to .sip.vonage.com
```
* **Inbound:** Famulor does **not** register via SIP REGISTER. Vonage sends calls through the **origination** to „Our SIP address".
* **Outbound:** Famulor sends calls to Vonage's **termination** SIP domain and authenticates with username and password.
## Prerequisites
* An active **Vonage** account with access to **Programmable SIP / Elastic SIP Trunking**
* At least one Vonage phone number (or a new number to purchase)
* A Famulor account
***
## Step 1: Create an Elastic SIP Trunk in Vonage
1. Open the **Vonage dashboard** and navigate to the **SIP** section.
2. Create a new SIP trunk and select **„Something else"** as the provider (i.e. not a preset provider).
***
## Step 2: Set up Termination (outbound calls)
**Termination** provides the SIP domain and credentials Famulor uses to send outbound calls.
1. Follow the **Termination** setup in Vonage.
2. Note the displayed values:
| Field | Example / meaning |
| -------------- | ---------------------------------------------------- |
| **SIP domain** | `.sip.vonage.com` (Termination SIP URI) |
| **User name** | Credentials for outbound calls |
| **Password** | Credentials for outbound calls |
Store the **SIP domain**, **username** and **password** safely. You need them in **Step 5** for the Famulor setup.
***
## Step 3: Set up Origination (inbound calls)
In **Origination** you define where Vonage forwards incoming calls – to **Famulor's SIP address**.
1. In a second tab, open Famulor at [app.famulor.de/phone-numbers?lang=en](https://app.famulor.de/phone-numbers?lang=en) → **Your phone numbers → + Integrate SIP trunk** and, under **Incoming call settings**, copy the value **Our SIP address** (e.g. `xxxxxx.eu.sip.livekit.cloud`).
2. Paste this address into Vonage under **Origination** as the **SIP-URI**.
Use the **exact** „Our SIP address" from Famulor – no spaces.
***
## Step 4: Assign a number to the trunk
Link a phone number to your Elastic SIP Trunk – either an **existing number** or a **newly purchased** one.
Note the Vonage number in **E.164 format** with country code (e.g. `+12025550123`). You need it in Step 5.
***
## Step 5: Set up the SIP trunk in Famulor
1. In Famulor, go to **Your phone numbers** and click **+ Integrate SIP trunk**.
2. Enter the data as follows:
| Field | Value |
| -------------------------------- | ----------------------------------------------------------------------------------------- |
| **SIP trunk type** | **Phone number (DID)** |
| **Phone number** | Your Vonage number in E.164 format (e.g. `+12025550123`) |
| **Username** | The **termination** username from Step 2 |
| **Password** | The **termination** password from Step 2 |
| **SIP address** (outbound) | The Vonage **SIP domain** from Step 2 (e.g. `.sip.vonage.com`, without port) |
| **Outgoing phone number format** | **International (with leading +)** |
| **Country** | The country of your Vonage trunk |
3. Under **Incoming call settings**, you'll see **Our SIP address** – the same address you entered as the Vonage origination in **Step 3**.
4. Click **Add SIP number**.
***
## Step 6: Assign an assistant and test
1. Open **Assistants** in Famulor and edit the assistant you want to use.
2. Select the correct **inbound type** (incoming calls).
3. Choose your connected Vonage phone number from the list.
4. Click **Save assistant**.
5. Place a **test call** to your Vonage number and check that the AI assistant answers.
***
## Call transfer to a human (warm transfer)
Famulor can hand off an ongoing call to a real person. **For Vonage, use the warm transfer only** – cold transfer does not work over the Vonage trunk (see the note below). For the general setup, see [Assistant call forwarding](/en/platform/assistant-call-forwarding).
**Vonage does not support SIP REFER.** Famulor performs **cold transfers** via **SIP REFER** – the carrier connects the caller onward directly. Because Vonage SIP trunks do **not** support REFER, **cold transfer over the Vonage trunk does not work reliably**.
**Recommendation for Vonage:** use the **warm transfer**. Famulor creates a **new SIP INVITE** (a separate outbound call through the Vonage trunk) and **merges the two calls** – this needs **no** REFER and therefore also works with SIP trunks that lack REFER support, such as Vonage.
### Transfer target: phone number or custom SIP
You specify the warm transfer target in one of two ways:
* **Supervisor phone number:** the contact's phone number (e.g. `+49 1512 3456789`).
* **(Advanced) Custom SIP/Extension:** enable this to specify a **custom SIP address or internal extension** instead of a phone number (field **Custom SIP transfer**, e.g. `sip:number@sip-server`).
### Warm transfer settings
| Field | Meaning |
| ----------------------------------------------------- | ----------------------------------------------------------------------------------------------------------- |
| **Supervisor phone number** / **Custom SIP transfer** | Transfer target: a phone number **or** – with **Custom SIP/Extension** enabled – a SIP address or extension |
| **Outbound phone number** | The number used to dial the supervisor (requires an outbound trunk) |
| **Caller ID shown to supervisor** | Which number the supervisor sees on the call (e.g. the outbound number) |
| **Hold music** / **Hold music volume** | Hold music played to the caller and its volume (0–100) |
| **When to transfer** | Describes when the AI should start the warm transfer |
| **Hold message** | What the AI says to the caller before placing them on hold |
| **Summary instructions** | How the AI should brief the supervisor (who is calling, why, why a human is needed) |
| **Briefing initial message** | The first message the supervisor hears |
| **Connected message** | What the caller hears once the supervisor is connected |
In **Summary instructions**, **Briefing initial message** and similar fields you can use variables: `{customer_phone}` (the caller's number) and lead variables such as `{name}` or `{email}`.
***
## Common issues
Check the **origination** in Vonage (Step 3): it must contain the **exact** „Our SIP address" from Famulor. Also make sure the **number is assigned to the trunk** (Step 4).
Check the **termination** values from Step 2 in Famulor: **SIP address** (`.sip.vonage.com`), **username** and **password**. Set the number format to **International (with leading +)**.
Always use the **exact** „Our SIP address" from Famulor (Phone numbers → Integrate SIP trunk → Incoming call settings).
**Vonage does not support SIP REFER**, which Famulor uses for cold transfer. Use the **warm transfer** instead – it creates a new SIP INVITE and merges the calls (no REFER), so it works with Vonage. Details: [Assistant call forwarding](/en/platform/assistant-call-forwarding).
***
## Help
If you need help, contact our support team at [support@famulor.io](mailto:support@famulor.io). For general guidance, see [SIP Integration](/en/provisioning/sip-ai/sip-integration) and [SIP integration issues](/en/troubleshooting/sip-integration-issues).