Call Forwarding

Call Forwarding is a telephony feature which redirects an incoming telephone call to another destination, which may be, for example, a mobile telephone, voicemail box or another telephone number where the desired called party is available.

The following call forwarding rules can be applied:

• Forward All Voice Calls - the incoming calls are immediately forwarded to the destination number you have selected whether you are busy in a call or not. This rule will override the next two rules.
• Forward No Answer - the incoming calls are forwarded to another number if you do not answer the call and No Answer Ring Duration timer expires.
• Forward Busy - the incoming calls are forwarded to another number when all lines are busy. This type of forwarding is also applied if you click Hang up button during an incoming call.

Fax Voip Softphone supports 2 different methods for implementing Call Forwarding – standard method and Hairpin Call Forwarding (2 call legs).

Standard Implementation (recommended)

When a call is forwarded, the message (302 Moved Temporarily, H.450.3) is sent back to the calling party requesting that the caller reoriginate a follow-on call to the forwarded-to destination.

The standard mechanism for Call Forwarding usually supported by VOIP PBX in local network. Nevertheless, these mechanism often does not work in public VOIP networks for different reasons. We recommend to use standard mechanism where possible.

Hairpin Call Forwarding (2 call legs)

This is an internal mechanism. In this case, a second independent VOIP call leg is created for the forwarded call leg. This leg is bridged to the original incoming VoIP call leg. This method has the advantage that it has no end-to-end dependency on the capabilities of the VOIP endpoints.

In this case the second call leg is created based on Outgoing VOIP Call Routing rules – the same rules that you use for standard outgouing calls.

The Hairpin Call Forwarding have no dependency on the capabilities of your VOIP network. Using these method you even can forward SIP calls to H.323 and vice versa.