Yeastar Blog | Multiple Registrations for One Number with SIP Forking

When we are off office, work from home, we don’t want to miss calls. So you may ask, is it possible to set up two or more terminals to ring simultaneous with one single call? Is it possible to have two phones with the same extension number? Or in other words, do you want to use your extension number with multiple phones, like your desktop IP phone and softphone in your smartphone? SIP Forking, an awesome feature that allows multiple registrations for one extension number so one single call ring two or more terminals at same time.

What is SIP Forking?

SIP forking refers to the process of “forking” a single SIP call to multiple SIP endpoints. This is a very powerful feature of SIP. A single call can ring many endpoints at the same time.

With SIP forking, you can register one extension number to multiple SIP endpoints, so to let your desk phone ring and mobile softphone ring at the same time, and you will be able to take calls from either device.

sip forking-chart

How does SIP Forking work?

It is used to have the same extension on two or more devices. With SIP forking you can have your desk phone ring at the same time as your softphone or a SIP phone on your mobile. For example, you would use SIP forking to ring your desk phone and your Android SIP Phone at the same time, allowing you to take the call from either device easily. In the same manner, SIP forking can be used in an office and allow the secretary to answer calls to the extension of his/her boss when he is away or unable to take the call.

User Jason working at the Marketing department uses the extension 1008. When necessary, he also works from home. He uses the following to communicate:

  • He has an automatically provisioned phone Yealink T26 in his office.
  • He has X-Lite softphone on his home computer.
  • He also uses a SIP client on his mobile phone.

SIP Forking in Yeastar S-Series VoIP PBX

Yeastar S-Series VoIP PBX fully supports SIP forking. SIP forking is a feature that enables an extension number to be registered by multiple SIP terminals simultaneously. The value of concurrent registrations limits how many sip endpoints the extension can be registered. The default limit in S-Series is 5.

Click “Settings” > “Add/Edit Extension”, and modify Concurrent Registrations.

sip forking-extension

Actually, except for the SIP forking feature, Yeastar S-Series VoIP PBX provides powerful mobility solution for road warriors and off-site employees. Like: