Call Forwarding allows incoming SIP calls to an FXS port to be redirected to another SIP URL.  Note that incoming PSTN calls (through the LINE socket) can NOT be forwarded, as discussed under “LINE port” below.

DrayTek have been adding Call Forwarding function to firmware for their VoIP routers.  In Vigor 2100V it is under “VoIP > SIP Related Functions Setup”, and in Vigor 2800V look in the menu on the “VoIP > Phone settings > index” page under “Call Feature” heading.  If your model does not support Call Forwarding, check whether a later firmware version is available for download.

1. Choose the Call Forwarding option:

  • “always” – all incoming calls will be redirected
  • “busy” – only redirect if this phone handset is being used
  • “no answer” – only redirect if this handset is not answered after the Time Out period.

2. Enter the number to redirect calls to in the “SIP URL” field.   See description below.  Note that you can forward the voip call to any other sip account. – but you must make sure the two sip providers can communicate with each other.

3. Enter the Time Out period.  This used for the “no answer” option.

Forwarding to regular phone or Mobile
To forward to a PSTN number (including a mobile phone), enter the SIP URL to forward to as <PSTN phone number> @ <your SIP provider>.  You can also simply enter the phone number, and this will use your default VoIP provider’s PSTN gateway.  Note that the forwarded call goes out your VoIP provider’s PSTN gateway on your account, so you pay for the PSTN/mobile call.

For example, assuming that the default VoIP provider for this port is Engin, the following settings will redirect to a cellphone (i.e. to if the phone isn’t answered after 15 seconds.

For example, to forward all incoming calls (without any delay) to mobile phone (0410 123456) using the SPANtalk VoIP provider enter

Multiple SIP accounts registered
The Vigor 2700V and 2800V models allow up to 6 SIP accounts to be registered; and so the incoming call may be from a different VoIP provider than the Call Forwarding uses.  If this is the case, it depends whether on the two SIP providers can communicate with each other.

Note: you can create a PhoneBook entry to check whether two sip providers can communicate with each other.

LINE port
Note that the LINE port on Vigor 2100V, 2500V and 2700VL models is for PSTN Loop-through only – it is NOT an FXO port, and cannot provide a gateway between PSTN and VoIP.  More specifically, incoming PSTN calls are NOT redirected using the Call Diversion feature.

There are many reasons why Call Forwarding might not work, including:

  • calls from PSTN (through LINE ports) cannot be forwarded.
  • your VoIP provider may not support Call Forwarding
  • The VoIP provider the call is coming from may not allow SIP calls to the VoIP provider you are forwarding the calls through.