# Register 2N IP Intercom with Cloud Voice Extension

A 2N IP intercom joins Cloud Voice the same way any SIP phone does: you hand it the credentials for a dedicated extension, and from then on the door station can dial your other extensions and be reached by them. All of the registration work happens in the intercom's own web interface, using an extension you set up earlier on the PBX.

:::note
SIP (Session Initiation Protocol) is the standard that phones and other devices use to set up calls. PBX (Private Branch Exchange) is your phone system, which in this case is Cloud Voice. Registering the intercom as a SIP endpoint simply means the intercom logs in to Cloud Voice as an extension, exactly like a desk phone or the Cloud Voice App would.
:::

## Before you begin

- [Create an extension for the 2N IP intercom](/pbx/integrations/2n-intercom/2n-ip-intercom-integration-preparation/#_2n-ip-intercom-integration-preparation__create-extension) on Cloud Voice, and have these details on hand:
  - The extension number, its registration name, and its registration password.
  - The domain name of your PBX and the SIP registration port.

    :::tip
    Unless you have changed it, the SIP registration port is `5060`.
    :::
- [Give the 2N IP intercom network connectivity](/pbx/integrations/2n-intercom/2n-ip-intercom-integration-preparation/#_2n-ip-intercom-integration-preparation__section_q2g_prj_ghc) so you can reach its web interface.

## Sign in to the intercom

1. Open a browser and enter the IP address of the 2N IP intercom in the address bar.
2. Sign in with the username `admin` and its password.
3. Select **Log In**.

![The 2N IP intercom sign-in page prompting for the admin credentials](/images/pbx/2n-login.png)

## Open the SIP settings

In the intercom's web interface, go to **Calling > SIP 1**. This is where you enter the account details for the Cloud Voice extension.

![The Calling section of the intercom web interface with the SIP 1 account page open](/images/pbx/2n-web.png)

## Enter the extension credentials

1. Turn on **SIP Account Enabled**.

   ![The SIP Account Enabled checkbox selected on the intercom](/images/pbx/2n-sip-enabled.png)

2. Under **Device Identity**, fill in the extension's identity.

   ![The Device Identity fields where the extension number and PBX domain are entered](/images/pbx/2n-device-id-device.png)

   - **Phone Number (ID)**: The extension number.
   - **Domain**: The domain name of your PBX.

3. Under **Authentication**, supply the registration credentials.

   ![The Authentication fields for the extension registration name and password](/images/pbx/2n-auth.png)

   - **Authentication ID**: The extension's registration name.
   - **Password**: The extension's registration password.

   :::caution
   The **Authentication ID** and **Password** must match the registration name and registration password set on the Cloud Voice extension exactly, including capitalization. The registration name is often different from the extension number, so copy it from the extension rather than assuming they are the same. A mismatch is the most common reason the intercom fails to register.
   :::

4. Under **SIP Proxy**, point the intercom at the PBX.

   
   ![Cloud Voice, the SIP Proxy fields set to the PBX domain and port](/images/pbx/2n-proxy-pce.png)

   - **Proxy Address**: The domain name of your PBX.
   - **Proxy Port**: The SIP port of the PBX (`5060` by default).

5. Under **SIP Registrar**, turn on **Registration Enabled**, then complete the fields.

   
   ![Cloud Voice, the SIP Registrar fields with the registration address, port, and expiry](/images/pbx/2n-reg-pce.png)

   - **Registrar Address**: The domain name of your PBX.
   - **Registrar Port**: The SIP registration port of the PBX (`5060` by default).
   - **Registration Expiry**: Set a registration interval, or keep the default.

   :::note
   Registration Expiry is how often the intercom re-registers with Cloud Voice to prove it is still online. A shorter interval recovers faster after a network blip but sends more traffic. If you are unsure, leave the default in place. The ports here must match the SIP port configured on Cloud Voice, or registration will fail.
   :::

6. In the bottom-right corner, select **Save**.

## Confirm the result

When the extension registers successfully, the **Registration State** of the SIP line reads **REGISTERED**.

![The SIP line showing a Registration State of REGISTERED on the intercom](/images/pbx/2n-registered.png)

## What to do next

[Configure Call and Door Release for PBX Extensions on the Intercom](/pbx/integrations/2n-intercom/configure-call-and-door-release-for-pbx-extensions-on-the-intercom/) so the door station rings the right extensions and unlocks the door on the matching code.