ASTERISK. Determination of the "intermediate" number phone when forwarding?

Question

Asterisk

I made the following scheme:
caller -> my mobile -> SIP number (ASTERISK)
When calling ASTERISK, it sees the caller's number.
It is required that ASTERISK (or perhaps some cunning cisca) determines not only the caller's number, BUT (most importantly) also my mobile number (from which forwarding to SIP is set).
Ready-made implementations already exist and function successfully. For example here: optiroam.ru/toursim

Answer 1

What you need in telephony is called RDNIS. If the operator that redirects you from mobile to SIP gives this information, it will be available in the asterisk function CALLERID(rdnis)

Answer 2

Does anyone know of such operators? In particular, I'm interested in the ability to make a call through ASTERISK, and the subscriber to whom you call would display my mobile number.

Answer 3

1. A call comes to the Asterisk server either through a Multiphone thread, or stupidly to a GSM modem.
2. In any case, CALLERID is determined.
3. Depending on which channel the call came from, the number of the caller is determined.
4. If you really need it, Asterisk “sums up” this information into a string, which it drives into CallerID, which it sends to the phone.
If this is exactly what you need, I can drive pieces of my dialplan here a little later: now I’m too lazy and I want to sleep…