Is there something similar to ngrok, but deployed on its own server?

Question

Software and Internet Services

Actually, everyone knows ngrok - you can raise tcp tunnels and connect to a PC where there are no white IPs, as if it actually exists, and at the same time traffic goes directly between two PCs (nat passthrough). I have a server with a dedicated IP and several bakeries with gray IPs, and I would like to stir up the semblance of ngrok and give each PC the opportunity to become a server, so to speak. Does anyone actually know the similarity of ngrok? Free.
ps I immediately say not VPN, not DMVPN, and you definitely need nat passthrough so that the traffic itself does not go through the server

Answer 1

What is "nat passthrough"? Ngrok works as a reverse tcp proxy and traffic goes through it.

where there are no white IPs, as if it actually exists, and at the same time traffic goes directly between two PCs (nat passthrough)

If you meant VPN pass-throught, then this router function has nothing to do with ngrok and traffic, it simply allows router clients to establish vpn connections.

and at the same time traffic goes directly between two PCs (nat passthrough)

does not go
To implement the above, use ssh tunnels or vpn.