We can easily connect via
ssh to the remote machine that has public IP.
But now I have a remote machine without public IP, and I need to connect to it from my machine that does have public IP. So that, remote machine should initiate this connection (add a client).
I need it because there is my grandfather on computer without public IP, and he needs help with his system sometimes.
In similar situation on Windows I've used VNC connection (by TightVNC), TightVNC server has an option "Add a client": user just entered client's IP (i.e. my public IP), my client is already in "listening mode", and when "server" adds a client, connection is initialized.
So, is it possible to perform the same trick with SSH connection?