What can be used to centrally monitor GSM sockets?

Question

Electronics

There are a couple of GSM sockets in service (they can send SMS about the status of whether there is 220V power or not) and the main SIM card, where SMS messages are sent from sockets. I wanted to make a centralized server where the states of all sockets would be sent and a graph or state table would be displayed by date and time when the electricity was turned off and when it was turned on.
What hardware and software means can be used to implement this? How difficult is it?

Answer 1

From the category of DIY:
1. Single-board computer on ARM: Raspberry, Orange, etc. If you have skills, you can replace it with ESP8266 / 32
2. SIM800 / 900 for receiving SMS
3. Find, modify ready-made scripts for receiving SMS (minimum knowledge of python / bash) via AT commands
4. Output in any desired form.
If you have skills, one evening lesson