For the SIP account registration:
- Sign into the web interface of the video system (By entering your private IP Address at your location)
- Go to the "Account" section as you can see in the picture below.
- Click on "SIP account" to the left.
You will have to create a SIP profile on your PBX and then enter the user & server information. Once this is completed click save to register it.
For more information on the Yealink VC 120 video system click here.