A method of securely controlling through a private network a computer protected by a hardware-based inner access barrier or firewall and configured to operate as a general purpose computer connected to the Internet, comprising: two separate network connections separated by an inner hardware-based access barrier or inner hardware-based firewall protecting a private network connection configured for connection to a private network of computers but not protecting a public network connection configured for connection to a public network configured to include the Internet, the method including the step of controlling at least one operation of the computer, the control being provided through the private network and the operation involving data and/or code transmitted through an out-only bus or channel. Another method includes the step of controlling an operation of a second or third private protected unit of the computer, the control being provided through a second or third private network, respectively.