# Introduction

> How Edesy SIP trunking works - termination trunks for outbound calls, SIP destinations for inbound calls, and what you need before you start.

Source: https://edesy.in/docs/sip-trunking/getting-started

Edesy SIP trunking has two halves. **Outbound:** your PBX or voice-agent platform sends a SIP INVITE to your Edesy termination trunk, and Edesy places the call on the Indian phone network. **Inbound:** a call to your Edesy number is forwarded as a SIP INVITE to the URI you choose. You can set up either half, or both.

## How it works

```
OUTBOUND  your PBX / agent  --SIP-->  tk-<id>.trunk.edesy.in:5070  -->  phone network

INBOUND   caller  -->  your Edesy number  --SIP-->  your SIP URI (PBX, LiveKit, Vapi, ...)
```

1. **Create an account** at [voice-app.edesy.in](https://voice-app.edesy.in) and top up the prepaid wallet.
2. **Complete KYC and buy a number.** KYC is needed before you can buy Indian numbers; review takes about 24 hours. The number is your caller ID for outbound calls and the number people dial for inbound calls.
3. **Create a termination trunk** for outbound calls. See [Create a Trunk](https://edesy.in/docs/sip-trunking/termination-trunks/create-a-trunk).
4. **Route the number to SIP** for inbound calls. See [Route a Number to SIP](https://edesy.in/docs/sip-trunking/inbound/route-a-number-to-sip).
5. **Test both directions** from the portal before you dial over the phone network. See [Test Calls](https://edesy.in/docs/sip-trunking/inbound/test-call).

## Key terms

| Term | Meaning |
|---|---|
| Termination trunk | A SIP endpoint Edesy issues to you. Your system dials *into* it to reach the phone network. |
| SIP host | The trunk's hostname, `tk-<id>.trunk.edesy.in`. Port `5070`, UDP or TCP. |
| SIP destination | A saved SIP URI that Edesy dials *out to* when a call arrives on your number. |
| DID | A phone number you own on Edesy, written in E.164 (`+91XXXXXXXXXX`). |
| BYOC | Bring your own carrier: route calls over a SIP trunk you already have with another provider. |

## FAQ

### Do I need my own carrier to use Edesy SIP trunking?

No. Edesy provides the Indian numbers and the calling minutes. Bring your own carrier is optional, for teams that already have a trunk elsewhere.

### Can I use one trunk for several voice-agent platforms?

You can, but one trunk per platform or environment is easier to manage. Each trunk has its own host, auth settings, concurrency cap and test history.

### Which caller ID can I send on outbound calls?

The SIP `From` number must be a number you own on Edesy. Other caller IDs are rejected with `403 Caller ID Not Authorized`.

### Does Edesy support TLS and SRTP?

TLS signalling and SRTP media are available on request. Contact support before you configure a TLS-only peer.

### Which codecs are supported?

G.711 μ-law (PCMU) and A-law (PCMA). Enable only those two on your side to avoid codec negotiation failures.

### Is there an API?

Yes. Trunks are managed with `/v1/trunks` and saved destinations with `/v1/sip-destinations` on `https://voice-api.edesy.in`, using `Authorization: Bearer sk_...`. Each page in this section shows the matching request.

### What does it cost?

Rs 0.50 per minute with a 60-second pulse. Unanswered calls are free. Prices exclude 18% GST. See [Pricing and Limits](https://edesy.in/docs/sip-trunking/getting-started/pricing-and-limits).