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

# Enterprise SIP Trunk

> Enterprise customers can connect their own SIP trunk to Ned to bypass per-minute telephony cost while calls still reach the AI. Enterprise plan only.

# Enterprise SIP Trunk

<Note>
  The SIP trunk connection is available on the **Enterprise plan only**. On other
  plans the feature is visible but locked — contact sales to upgrade.
</Note>

Connect your **own SIP trunk** to Ned so your existing telephony carries the
calls — bypassing our per-minute PSTN cost — while inbound calls still reach
your AI agent exactly as they do today.

## How it works

Your SIP trunk sends calls to a dedicated, IP-authenticated SIP connection we
provision for your account. That connection is bound to Ned's voice engine, so
an inbound trunk call arrives as a normal inbound call and the AI assistant
starts on the leg — no change to how your agents behave.

## Prerequisites

To connect a SIP trunk you'll need:

* **One or more static public IPv4 addresses** for your SIP infrastructure —
  connections are authenticated by IP allowlist. CIDR ranges and dynamic IPs are
  not supported; each source must be a single IPv4 address.
* **TLS 1.2 or 1.3** for SIP signaling and **SRTP** for media (encrypted
  end-to-end).
* A trunk that supports at least one of the following codecs:
  **G.722, G.711 µ-law (PCMU), G.711 A-law (PCMA), G.729, Opus**.
* You operate your own SIP trunk and carrier; Ned does not resell the
  underlying telephony.

## What it does — and doesn't — save

<Warning>
  The savings are on **telephony only** — the per-minute PSTN cost your trunk
  replaces. The **AI/media** portion of a call (speech-to-text, the model, and
  text-to-speech) is still billed as usual. SIP is economical for **high-volume**
  traffic; for low usage a standard number is usually cheaper.
</Warning>

## Setting it up

1. On the **Enterprise plan**, open **Phone Numbers** and find **Enterprise SIP
   trunk**.
2. Enter your static source **IPv4 address(es)** (one per line) and
   select **Connect SIP trunk**.
3. Point your SIP trunk at the connection details we provide and place a test
   call to confirm it reaches your agent.
4. To change the allowlist later, use **Edit IPs**; to remove the trunk, use
   **Disconnect**.

## Security

* **IP authentication** — only calls from your allowlisted IPs are accepted.
* **Encrypted signaling + media** — TLS + SRTP.
* Standard anti-toll-fraud protections apply; outbound is rate-limited per
  source IP.