How to establish a computer-to-computer connection?

Question

VPN

I have a computer COMP_Server with a white IP and two computers COMP_1 and COMP_2 behind NAT on different networks. All computers (including COMP_Server) are running Windows 7.
My task is to create a direct tunnel between COMP_1 and COMP_2 using COMP_Server, how can I do it programmatically ?
Tunnel encryption and authorization on the server are not required, but not prohibited.
Hamachi is no good. You can use any programming languages/modules/libraries, etc.
If you offer Open VPN, then please show examples of implementation.
PS I dug up the solution, but I can’t implement it, I stumbled on compiling the driver, I will be very grateful if you chew it or suggest your own implementation method.

Answer 1

Install OpenVPN openvpn.net/index.php/open-source/documentation/howto.html
in its config, uncomment
client-to-client
so that clients can see each other
and in order not to add a bunch of clients but issue one certificate to everyone, you can use
duplicate-cn
true I did not use it, I cannot tell how clients will define each other in this case. and in the case of personal certificates, pairs certificate - ip will be written to the file

Answer 2

I'm not sure if several clients can connect at once, but it's still worth a try

Answer 3

If it is possible to forward ports through NAT, then look at rinetd

Answer 4

Why doesn't hamachi work?
If you have many clients, I recommend that you immediately think about full mech routing. OpenVPN does not know how to do this, I recommend tinc.
If, nevertheless, full mech is not needed, then use OpenVPN with one key for all. And you don't need to compile tap/tun, they come with openvpn

Answer 5

Vintage: we had experience connecting computers via RS232 via COM ports) Even NFS Porche almost did not lag on such a network)