Outgoing call and when the phone is switched off or unreachable

On our system incoming calls are forwarded to external numbers (Mobile phone or land lines). Which is working fine. There are couple of phone numbers. The system rings one by one. If the first one does not receive the call then it goes to the second one.

But the problem is if a number is switched off then the provider plays back a audio message which says something like “The number is not available right now…”. They play the message couple of time and then the line disconnects. After that our application rings the next number.

Problem is the playback message from the provider is too long for the user to wait for the next number.
Is it possible to ring the next number as soon as we identify that the current number is switched off or unreachable? Does mobile phone operators send any code in reply before the audio playback? Can we identify it in Asterisk?

Thanks in advance.

You will need to ask the network provider. We can’t even tell if this is being sent as normal or early media.

Anything that we can do with the SIP log?

You can see whether the call is being answered.

Hi David,
That is what I was thinking. Looks like the PSTN provider sends message after playing back the “The number is not available right now…” audio multiple times.

Any suggestion how we can see if the call is being answered? Like we wait a certain time and then check if the call was answered or not? Can we do that with some function/macro?

Thank,s in advance. Please excuse the basic question as I am new to Asterisk.

The only solution (from user point of view) is to play a music file as ring-back tone. This will suppress any looping message before the call is answered.