A2Billing: Setting up your SIP trunk, the final guide
Last modified: September 16, 2021

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. 2. If your termination provider requires the ‘Register’ field enter the register line under the existing [general] section – » Read more: A2Billing: Setting up your SIP trunk, the final guide »