Applies to VoipNow 3 and higher!
This article describes the SIP trunking feature and how to use it to connect a PBX to an extension. Also, it includes a set of recommendations with examples for seiting up Asterisk to act as a PBX.
Enable SIP Trunking for a VoipNow extension
When enabled at extension level, this VoipNow feature allows you to connect a PBX to the extension (when a DID assigned to that extension is called, it is passed further to the PBX in the SIP:To header). This option was added because some customers wanted to connect different PBX systems to VoipNow.
In order to enable this feature, you need a SIP trunking license. If the license is valid, in the Extension → Provisioning and SIP page, under the SIP Preferences area, you'll find the PBX is connected to this extension  Enable for SIP trunking service option. Select this checkbox, and you will be able to connect a different PBX to that extension.
How to configure Asterisk to act as a PBX
For this, you will need Asterisk box. There are plenty of installation tutorials on the web, so you shouldn't find any difficulty in installing Asterisk.
In our example,
./configure --prefix=/opt is used to set
/opt/ as a destination directory for the Asterisk files.
After completing the installation process, you will need to edit the files below:
The example above registers the local Asterisk PBX to the VoipNow system using extension
0003*001. Make sure the extension has SIP trunking enabled on the VoipNow server.
5000 is a local Asterisk extension that will be used for both incoming and outgoing calls.
This is a basic example of Asterisk dialplan that can place outgoing calls and receive incoming calls.
5000 is the only local extension. The rest of the prefixes matching
_X. get forwarded through the
mysip channel. The
[from-voip-provider] context is used for incoming calls.
To launch Asterisk, run the following:
Test the configuration
For example, if you want to register the
5000 extension using a X-Lite softphone, you need to open its SIP accounts → Properties menu page and set:
- User name: 5000
- Password: secret
- Authorization user name: 5000
- Domain: asterisk_server_ip
To call a different extension (e.g.
0003*002) from the Asterisk PBX, you need to simply dial
To take incoming calls via VoipNow on extension
[from-voip-provider] context needs to be added. When configuring your
/opt/etc/asterisk/extensions.conf file, you must replace the
18002304043 example with the DID number assigned to your account by your SIP provider.
18002304043 is a DID number assigned in the VoipNow interface for the specific extension with enabled SIP trunking.
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