A2Billing: Setting up your SIP trunk, the final guide

Last modified: September 16, 2021

A2billing sip trunk settings

A2Billing SIP trunk authentication can be performed via Digest (Username/Password) and via IP authentication. This article explains how to authenticate your SIP trunk in A2Billing using “Digest” Username/Password authentication.

A2Billing Username/Password based SIP authentication

When using username/password authentication on the SIP provider the SIP trunk has to be setup manually in Asterisk. We will give that SIP trunk a name and then use that name, instead of the IP address, in the A2Billing SIP trunk setup screen above.

Here’s an example of setting up A2Billing SIP trunk with Switch2VoIP. Many providers will be similar and provide all the connection details you need to enter. These settings go in the file /etc/asterisk/sip.conf.

1. Login to A2Billing dashboard. A2billing sip trunk settings 2. If your termination provider requires the ‘Register’ field enter the register line under the existing [general] section –

3. Then enter the SIP trunk settings details below. Here we are calling the trunk ‘switch2voip’. This will be used as the ‘IP Address’ in the A2Billing trunk set up page –

[switch2voip] canreinvite=no context=default host=5.9.126.75 secret=mypassword type=peer username=myusername disallow=all allow=ulaw fromuser=myusername trustrpid=yes sendrpid=yes insecure=invite nat=no

4. Next, apply those settings by running a ‘sip reload’ in Asterisk –

[root@a2b100 ]# asterisk -rv a2b100*CLI> sip reload a2b100*CLI> exit

5. Now we can set up the trunk in A2Billing, using the name we specified above, instead of the IP address –

A2b setup a2billing trunk

External resources

  1. SIP trunking configuration
  2. Setup SIP trunk on Asterisk, Vicidial and Goautodial
  3. A2Billing free and Open Source Billing Softswitch Solution for Asterisk