We wrote this guide after testing the OpenVox UC300/500 IP-PBX on firmware Version 2.4.2. More information on OpenVox UC Series IPPBX can be found on the Openvox website.
Add a RingOffice SIP Trunk
Navigate to PBX > Trunks, select SIP Trunk after that click Add to create a new SIP trunk so that you can send calls out to and receive calls in from that system/device.

Required parameters for your RingOffice SIP Trunk:
Trunk Mode: Client
Trunk Name*: Enter any name to identify your RingOffice trunk
Host*: sip.ringoffice.com (RingOffice primary SIP server)
Username: SIP Authentication ID provided by RingOffice
Secret: SIP Authentication Password provided by RingOffice
Please find the filled SIP parameters in the screenshot below:

The Register String is generated automatically. Other parameters can be left as default.
Create Extensions
In the UC series IPPBX, 10 SIP extensions are preset for users. You can add or edit extensions as needed. Navigate to PBX > Extensions > Extensions, select SIP Extension and click Add to create a new SIP extension. You will need to set the extension number, name, password, voicemail, extension settings, and other options.
Here are the required parameters for Extensions:
User Extension: Extension number assigned to this user
Display name: The CallerID name to be shown on outgoing calls from this user extension.
You may set other advanced settings as needed. Default parameters are already set up correctly.

Set Up Inbound Routing
The default inbound route destination in the UC300/UC500 is a ring group that includes the 10 preset SIP extensions. To edit inbound routing or add a new route, navigate to PBX > Call Control > Inbound Routes. Here you can define how to route incoming calls to your system on any trunk, including defining expected DID&CID numbers, inbound destinations, and so on.

Set up Outbound Routing
Outbound Routes tell your phone system which numbers your phones can call and which Trunk to send these calls through. To manage outbound call routing, navigate to PBX > Call Control > Outbound Routes. Here, you can edit the default outbound route and select the RingOffice SIP trunk you just created.
