---
title: "Your phone system. Connected through Bird."
canonical: "https://bird.com/voice-api/features/sip-trunking"
---

# Your phone system. Connected through Bird.

Connect a PBX or SIP client with explicit authentication and call directions. Keep inbound routing and outbound policy under your control.

## Your phone system. Connected through Bird.

Bring your PBX or SIP client. Set the direction, authenticate the connection, and choose where calls can go.

Illustrative SIP configuration. No trunk settings change and no call is placed.
[Caller IDs](/docs/guides/voice/caller-ids)[Incoming calls](/docs/guides/voice/receiving-calls)
[Explore SIP trunks](/docs/guides/voice/sip-trunks)

## Open the directions you intend to use.

Connect your phone system to the telephone network.

### Authenticate the client.

A new trunk starts with both directions off. Configure the permitted public IPs, API keys or session credentials and use the SIP domain assigned to the trunk.

### Prepare incoming delivery.

Enable inbound calling, add a delivery gateway and route a Bird number to the trunk. Turning inbound off resets associated number routes to reject; turning it on again does not restore them.

### Separate transport and call policy.

SIP supports UDP or TCP on 5060 and TLS on 5061. TLS protects signaling; it does not by itself establish media encryption. Outbound calls also need an eligible caller ID and enabled destination.

[Explore Voice sip trunking →](/docs/guides/voice/sip-trunks)

## Keep building with Voice.

Complete the number route, calling identity and destination policy around the trunk.

[Incoming calls Route calls to the right destination. →](/voice-api/features/inbound-routing)

[Caller IDs Verify the identity customers see when you call. →](/docs/guides/voice/caller-ids)

[Global calling Prepare destinations and limits before placing calls. →](/docs/guides/voice/destinations)

[Explore Voice →](/voice-api)

## बिना नियंत्रण खोए स्केल करें।

टीमों को वर्कस्पेस में व्यवस्थित करें, API एक्सेस नियंत्रित करें, और ऑडिट लॉग से बदलावों को ट्रेस करें।

[वर्कस्पेस](/docs/guides/workspaces)[टीम की भूमिकाएँ](/docs/guides/users-teams-roles)[API प्रमाणीकरण](/docs/guides/authentication)
[Enterprise जानें](/enterprise)

## Start with Voice. Build across channels with Bird.

[Get Started](/dashboard/signup?returnTo=%2Fdashboard%2Fw%2Fvoice%2Fonboarding) · [Contact Sales](/demo?product=voice)

[Email](/email-api) · [SMS](/sms-api) · [WhatsApp](/whatsapp-api) · [Apple Messages](/apple-messages-api) · [Voice](/voice-api)



## Related resources

- [Voice overview](/docs/guides/voice/overview) (docs)
- [What is a voice API?](/explained/voice/what-is-a-voice-api) (answer)

[Get an implementation brief](/learn/workspace?topic=voice)