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

# Connect Airtel to Bolna with a SIP trunk

> Bring your Airtel numbers to Bolna: get the SIP trunk details from Airtel, create a Custom SIP trunk in Bolna and give Airtel the values to send calls to Bolna.

[Airtel Business](https://www.airtel.in/business/b2b/sip-trunk) sells SIP trunks. Airtel has no carrier preset in Bolna, so you connect it as a **Custom** SIP trunk.

> [!NOTE]
>
> Airtel does not publish its SIP trunk settings, so your Airtel Business account team sets up their side. Send them the values in [What to send Airtel](#what-to-send-airtel).

## Before you begin

Get these from your Airtel Business account team:

* **An Airtel SIP trunk** with at least one Airtel phone number on it.
* **The host and port Bolna dials** for outbound calls.
* **The IP addresses Airtel sends calls from.**
* **A SIP username and password**, if Airtel authenticates the calls Bolna places with credentials instead of Bolna's IPs.

## What to send Airtel

Ask Airtel to send calls for your numbers to Bolna and to accept calls from Bolna:

| Bolna value | |
| - | - |
| Address for inbound calls | `trunk.bolna.ai`, port `5060` |
| Transport | `UDP` or `TCP`, not TLS |
| Codecs | `PCMU` and `PCMA` |
| Bolna signalling IPs | `15.252.21.46` and `13.206.230.198` |

The [SIP trunk overview](https://www.bolna.ai/docs/sip-trunking/overview#how-a-call-flows) lists the media ports.

## Create the trunk in Bolna

**1. Pick Custom**

In the sidebar, under **Deploy**, open **SIP Trunks** and click **Create trunk**. If your account still has legacy SIP trunks, click **Open new SIP trunks** first. On the **Provider** step, pick **Custom** and enter a **Trunk name** and the number of **Channels**.

If Airtel's port is `5060`, enter the host in **Gateway we dial**. If it is any other port, leave the field empty: it always uses port `5060`, so you add the gateway after the trunk is created. Click **Continue**.

**2. Add Airtel's IPs and credentials**

On the **Carrier IPs** step, add each IP address Airtel sends calls from. Bolna accepts an inbound call only from these addresses.

If Airtel gave you a SIP username and password, enter them under **Carrier credentials (optional)**. Click **Continue**.

**3. Add your Airtel numbers**

On the **Numbers** step, enter each Airtel number in E.164 format, for example `+91XXXXXXXXXX`, and click **Add**. Click **Continue**, check the summary and click **Create trunk**.

**4. Add the gateway if needed**

If you left **Gateway we dial** empty, open the trunk's **Connection** tab. Under **Outbound: gateways**, click **Add gateway** and enter Airtel's **Host** and **Port**, with **Priority** `1`.

For every field on these steps, see [Connect your carrier](https://www.bolna.ai/docs/sip-trunking/connect-carrier.md).

## Assign an agent and test

* **Inbound:** open the trunk's **Numbers** tab and, in the **Agent** column, pick an agent for your Airtel number. Then call the number. See [Receive inbound calls](https://www.bolna.ai/docs/sip-trunking/inbound-calls.md).
* **Outbound:** on the agent's **Calling** tab, set **Telephony Provider** to **SIP Trunk**. In the agent's outbound call dialog, pick your Airtel number as the caller ID, enter the number to call and click **Place call**. See [Make outbound calls](https://www.bolna.ai/docs/sip-trunking/outbound-calls.md).

If a call does not connect, see [Troubleshooting](https://www.bolna.ai/docs/sip-trunking/troubleshooting.md).


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