# Switch Extension Presence by Function Key

Presence tells the rest of your organization whether an extension user is available, busy, away, and so on. Instead of opening a menu each time their availability changes, users can flip to a preset presence with a single function key (a programmable button on the phone or in the app). This page walks through defining those keys in the web portal and pushing them out to an IP phone (a desk phone that registers over the network).

## Before you begin

- Your Cloud Voice system must be running firmware `84.20.0.74` or later.
- To use these keys on a desk phone, the IP phone has to be provisioned through Cloud Voice and already assigned to an extension. For provisioning instructions, see:
  - [Auto Provision IP Phones Remotely via RPS Method](/pbx/administrator-guide/auto-provision-ip-phones-remotely-rps-method/)
  - [Auto Provision IP Phones Remotely with Proxy](/pbx/administrator-guide/auto-provision-ip-phones-remotely-with-proxy/)

:::note
The **Set Presence** function key type is available only on firmware `84.20.0.74` and later. If you do not see this option in Step 1, confirm the system firmware before continuing.
:::

## Step 1: Define the function keys on the extension

1. Sign in to the web portal and go to **Extension and Trunk > Extension**, then open the extension you want to edit.
2. Select the **Function Keys** tab.
3. Add a key for each presence the user should be able to switch to:
   - **Type**: Choose **Set Presence**.
   - **Value**: Pick the target presence from the drop-down list. This is the presence the key will switch the extension to when pressed.
   - **Label**: Optional. Any text you enter here appears on the phone display.
4. Click **Save**.

:::tip
Give each key a short, clear **Label** (for example, `Lunch` or `Do Not Disturb`) so the user can tell at a glance what each button does. You will want one key per presence the user switches to often.
:::

![Cloud Voice, Function Keys tab with a key set to Type "Set Presence" and a presence chosen in the Value list](/images/pbx/set-extension-presence-function-key.png)

## Step 2: Push the keys to the IP phone

If the extension is tied to a provisioned desk phone, re-provision it so the new keys take effect. Skip this step if the user only uses the Cloud Voice App, which picks up the keys automatically.

1. Go to **Auto Provisioning > Phones** and click the refresh icon ![refresh](/images/pbx/refresh.png) next to the phone. The system asks whether you want to re-provision it.
2. Click **OK** in the confirmation window.

:::caution
Re-provisioning reloads the phone's configuration, which can briefly interrupt service on that device. When possible, do it while the extension is not on an active call.
:::

## What the user sees

**Cloud Voice App**

The new keys appear in the app's function key list. The user changes presence by clicking the corresponding key.

**IP phone**

The keys are loaded onto the phone as BLF (Busy Lamp Field) keys: buttons with a status light. Pressing one switches the extension to that presence. The BLF LED (the light on the key) reflects the current state:

- **Solid green**: the extension is currently set to the presence tied to that key.
- **Solid red**: the extension is set to a different presence.

:::note
A BLF key does double duty here: it both switches the presence when pressed and shows, through its LED color, whether the extension is currently in that presence. After re-provisioning, a lit LED is a quick way to confirm the key loaded correctly.
:::