SIP

VoiceLink SIP trunking for Bolna AI voice agents

Connect VoiceLink to a Bolna voice agent as a Custom SIP trunk on port 3300, so the agent answers and places calls on your VoiceLink numbers in India.

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Official Documentation

At a glance

How VoiceLink SIP Trunking fits in the stack

Best for

Making and receiving real phone calls at production scale.

Use this layer when

You need numbers, trunking, call routing, or carrier control.

Connects to

STT, LLM, TTS, and workflow actions inside the live call.

Voice Stack

Telephony is the calling layer

This provider connects Bolna to the phone network. It controls how calls start, where they route, which numbers you use, and how the audio enters your agent pipeline.

TelephonyPhone Network

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STTListener

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LLMReasoning

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TTSVoice

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ToolsActions

Last updated 25 October 2026

What is VoiceLink SIP trunking used for in a Bolna voice agent?

VoiceLink SIP trunking connects your VoiceLink numbers to a Bolna voice agent, so the agent answers calls to those numbers and calls out from them through VoiceLink. VoiceLink is an Indian telephony provider with no carrier preset in Bolna, so you connect it as a Custom SIP trunk. VoiceLink listens on port 3300, so its gateway is added after the trunk is created.

How do I set up a VoiceLink SIP trunk with Bolna?

Have your VoiceLink SIP username and password, at least one VoiceLink number, and the IPs VoiceLink sends calls from. Ask VoiceLink support for the IPs if they are not in your account.
In Bolna, under Deploy, open SIP Trunks, click Create trunk and pick Custom. Enter a trunk name and channels, and leave Gateway we dial empty.
On the Carrier IPs step, add VoiceLink's IPs. Enter your VoiceLink SIP username and password under Carrier credentials (optional).
Add your VoiceLink numbers in E.164 format, such as +91XXXXXXXXXX, and create the trunk.
On the trunk's Connection tab, click Add gateway and enter host sip.voicelink.co.in, port 3300, priority 1.
In VoiceLink, open Voice Services > SIP Trunks > Create SIP Trunk. If Bolna is not in the Bot Provider list, select Custom and enter host trunk.bolna.ai, port 5060, UDP or TCP, and PCMU or PCMA.
In Call Routing > Create Routing, select your number and set Inbound Call and Outbound Call to SIP Trunk with the new trunk.
In Bolna, assign an agent to each number, and set the agent's Telephony Provider to SIP Trunk for outbound calls.

Every field is in the VoiceLink SIP trunk setup guide in the Bolna docs.

Which values connect VoiceLink and Bolna?

Setting	Value
VoiceLink gateway in Bolna	`sip.voicelink.co.in`, port `3300`, priority `1`
Bolna SIP server in VoiceLink	Host `trunk.bolna.ai`, port `5060`
Transport	UDP or TCP, not TLS
Audio format	`PCMU` or `PCMA`
Bolna IPs, if VoiceLink asks	`15.252.21.46` and `13.206.230.198`
Authentication	Your VoiceLink SIP username and password as carrier credentials
Bolna preset	None. Use Custom

What can you build with VoiceLink SIP and Bolna?

AI agents on VoiceLink numbers. Route a VoiceLink number to the trunk and have a Bolna agent answer it, or set a default agent for every number on the trunk.

Outbound calls from your VoiceLink numbers. Place single calls or batches with a VoiceLink number as caller ID.

Caller details in the prompt. Inbound calls fill from_number and to_number, and mapped SIP headers can add more variables.

Check the connection without an agent. Test trunk places an echo call in each direction, so you can confirm VoiceLink's setup before going live.

For other carriers, see the generic SIP trunk page.

FAQ

VoiceLink SIP Trunking on Bolna: frequently asked questions

Yes, over a SIP trunk. VoiceLink has no carrier preset in Bolna, so you create a Custom SIP trunk with your VoiceLink SIP username and password.

Add the gateway sip.voicelink.co.in on port 3300 with priority 1, on the trunk's Connection tab after you create it. The Gateway we dial field in the create flow always uses port 5060, so leave it empty.

Select Custom and enter SIP Server Host trunk.bolna.ai, SIP Server Port 5060, UDP or TCP transport, and PCMU or PCMA as the audio format.

VoiceLink's guide shows Bolna's legacy SIP trunks page. Accounts without legacy trunks see the new SIP Trunks page, so follow Bolna's VoiceLink guide.

Other providers in this layer

Telephony

Exotel

Exotel lets a Bolna voice agent make and answer phone calls in India on your own ExoPhones, routed and billed through your Exotel account.

Telephony

Plivo

Plivo connects a Bolna voice agent to Indian phone numbers for inbound and outbound calls. Buy a number in Bolna or bring your own Plivo account.

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Twilio

Twilio lets a Bolna voice agent make and answer phone calls outside India. Buy a US number in Bolna or connect your own Twilio account and numbers.

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See where VoiceLink SIP Trunking fits in your production workflow

Use the demo to walk through provider selection, stack tradeoffs, and the exact workflow you want Bolna to automate.

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