A2Billing is a great piece of call billing software for Asterisk. It can be integrated with FreePBX and used in lots of different ways.
I run my own Asterisk system with FreePBX and use a2billing to do least cost routing. It’s possible to import rate tables from many different voip providers and then let a2billing route the call based on the cheapest route.
One of the things you need to be aware of is that a2billing will route based on the ‘best matching’ rate. So, lets say you are trying to call +17061234567 and you have rate cards for 2 providers. If provider_a has a rate for +17061 at $0.02/min and provider_b has a rate for +1706 at $0.01/min, a2billing will choose the more expensive provider_a as the rate is a better match. This could require some manipulation of the rate tables to get things to work how you want.
As I said a2billing can also integrate with FreePBX so that you can pass all outgoing calls from FreePBX to A2Billing to allow it to do the routing. You also get the benefit of better CDR reports.
So, if you’re looking for something to do least cost routing for Asterisk then it might be worth checking out a2billing!
When I setup my ratecard here I only created 1 rate to Leicester in the UK. Ok for testing but not much use in the real world! So how are we going to enter all of the rates we need – the answer is to import them. Many ITSP (Internet Telephony Service Providers) publish a rate file that you can download. I’m going to use the callwithus (my provider) rate file that you can download from here.
One of the great things about voip is that you can make international calls at local rates. Combine that with Asterisk/FreePBX and you’ve got the ability to make cheap international phone calls using your mobile phone.
To do this we’re going to setup DISA (Direct Inward System Access). This will enable us to ring our Asterisk server, get a dial tone and then dial back out again.
Then I will show you how you can combine this with callbacks if that works out cheaper for you.
Installing the modules
First we need to install the DISA (if it’s not installed already) and Callback modules. See part 5 for more information about installing FreePBX modules.