VPN tunnel with an EC21

Hi,
Is it possible to setup a VPN tunnel with an EC21 without software running on any external hardware?

I have an EC21 that provides internet access to another module, currently just sending data over TCP. This module has a user interface that I would like to be able to remote access via the internet connection provided by the EC21 but I cannot access the module to host any software on it. Is there any way to make this system work?

Any suggestions would be appreciated.
Thanks
Charlie

Hi @charlieR
I don’t quite understand. Do you use a regular SIM card or a dedicated SIM card? Regular SIM cards should be able to access the Internet normally,