PSTN mode (Public Switched Telephone Network) goes over the exchange and not over SIP. One trunk line is seized for internal calls and two trunk lines for external calls

configuration OT


A new user is created at the OT:

  • Log on to OV8770 and go to “Users”
  • then right-click on “Create User”
  • create a new user for PSTN

after the new user has been created, right-click on the user

  • Associate SIP device
  • new
  • Create any mobile

  • Allocate free number for the user

  • go to the tab OT configuration
  • there under “Licenses” check “Off Site mobility” and “Advanced Telephony API”

  • connect to the PABX
  • continue to the users
  • Concerning user
  • Remote extension
  • Enter external number

Configuration sys collection management


  • perform the synchronization in sys-Collection Management
  • then the newly created user appears with the new phone number
  • assign and save a license for this user

Configuration Client


After starting the client and successfully registering, you can now see the number created as the active line

you can also change the external number directly in the client