All infos on: http://weigu.lu/microcontroller/smartyReader/index.html
Because of the EU Energy Efficiency Directive from 2012 the gas and electricity Distribution System Operators (DSO) in Luxembourg replaced there gas and energy meters with smartmeters (named smarty :() from Sagemcom (T210-D).
As it seems the same smartmeters are deployed in Sweden, parts of Austria and the Netherlands.
These smartmeters have a user port that delivers 10 second data (RJ12 connector under the green lid). The P1 data output communication protocol and format is specified in the Dutch Smart Meter Requirements v5.0.2 . The solution deployed in Luxembourg includes an additional security layer standard that is conform to the IDIS package 2.0 requirement. The encryption layer is based on DLMS security suite 0 algorithm: AES128-GCM. More information can be found in this document.
The Smartyreader is a simple board designed with KiCAD and decrypting the smartmeter data with an ESP8266 (Lolin D1 mini pro). The data is then published over MQTT via WiFi or Ethernet. A new version allows also to use LoRa or LoRaWAN.
For infos from the newest software look here: https://github.com/weigu1/SmartyReader/tree/main/Arduino/SmartyReader_P1_WiFi_Ethernet.