How to set up outgoing calls through an idle modem?

Question

Asterisk

There is an asterisk 11.7, as well as a couple of e1550 dongles.
I want to add a few more dongles of the same operator, combine them into a group, and so that during outgoing calls the modem is selected from the list of possible idle modems.
Now like this:
The modem is selected depending on the direction of the call

exten => _09[678]XXXXXXX,1,Dial(dongle/i:3519110431XXXXX/${EXTEN})
exten => _09[678]XXXXXXX,2,Hangup

As you can see, outgoing calls to a specific operator are tied to a modem.
Ideally, there would be several groups (kyivstar, life ... etc.) with 2-3 dongles for each operator

Answer 1

Here we consider a situation similar to yours
https://habrahabr.ru/post/180445/