Camp on to a Busy Extension

Busy Camp-on feature allows a caller to place a call reservation when he or she makes a call to an extension and receives a busy signal. The PBX will automatically call the caller back as soon as the called extension becomes available.


  • The Busy Camp-on feature is only applicable for the calls between extensions.
  • The timeout for a Busy Camp-on request is 3600 seconds. This means that the PBX will not call the caller back if the called party is still unavailable 1 hour after the request is initiated.
  • A maximum of 10 Busy Camp-on requests is available for each extension. If exceeds, the PBX will cancel the earliest requests.


Assume that extension 1000 makes a call to extension 2000, but extension 2000 is in a call.

In this case, extension 1000 can hang up the call and camp on to extension 2000 by dialing a feature code. The PBX will call extension 1000 back and connect it to extension 2000 as soon as extension 2000 becomes available.

  1. Extension 1000 dials *792000 to camp on to extension 2000.
    Tip: The default feature code for enabling Busy Camp-on is *79. You can change, enable, or disable the code on PBX web portal: Call Features > Feature Code > Busy Camp-on > Enable Busy Camp-on.

    A prompt "The Busy Camp-on has been enabled" is played and the call is hung up automatically.

  2. As soon as extension 2000 becomes available, the PBX will call extension 1000.

    Extension 1000 receives an incoming call pop-up with caller ID displayed as Busy Camp-on {name_of_called_extension}{number_of_called_extension} and will hear a prompt "This call is connected via Busy Camp-on feature" after answering the call.

  3. The PBX calls extension 2000.

    After extension 2000 answers the call, extension 2000 and extension 1000 are connected.