Siemens SIMATIC S7-1200 CP 1243-8 IRC Operating Instructions Manual page 27

Telecontrol communication - Internet
In the sample configuration shown, an S7-300 and two S7-1200 stations communicate with a
master station SINAUT ST7cc/ST7sc via the Internet.
The CPs are connected via their Ethernet interface.
VPN tunnels are established via the ADSL router SCALANCE M812.
Figure 1-3
CP 1243-8 IRC
Operating Instructions, 02/2018, C79000-G8976-C385-03
Communication via the Internet with VPN tunnels
Application and functions
1.9 Configuration examples
27