Busy Lamp Field (BLF) allows you to see on a fixed device whether a user is on a call. Particularly suited to environments where offices are divided into several rooms or where people work in different locations, BLF helps you improve your accessibility and the quality of your service.

On a user’s telephone, a BLF hotkey can be programmed for an extension; when the extension is available, the BLF hotkey lamp is off; when a call rings on the extension, the BLF hotkey lamp flashes; and when the extension is busy, the BLF hotkey lamp is on continuously. When a call rings on the extension, the call can be picked up by pressing the BLF key. The number of BLF hotkeys you can use is limited by the number of hotkeys that can be programmed on the extension, by using extension modules you can increase the number of hotkeys available. However, to be able to see the BLF status of other users, you must have been assigned the appropriate rights in a privacy group, see 6.3 Privacy groups.