Patent ID: 8032936

Claim:
A system, comprising: a deterministic network; a computer executing a hard real-time operating system, said computer being connected to the deterministic network; an application running under the hard real-time operating system; a security process running under the hard real-time operating system; and an external monitor connected to the deterministic network, wherein the security process is configured to periodically, in hard real-time, check the integrity of the application and/or a data element used by the application and, if the integrity check of the application or the data element indicates that the application or data element has been tampered with, notify a user of the system and/or shut down at least part of the system or application, and the security process includes a challenge handler that is configured to (i) receive a challenge transmitted from the external monitor to the challenge handler via the deterministic network and (ii) transmit to the external monitor via the deterministic network a response to the challenge within a specified hard real-time interval, wherein the external monitor is configured so that if the external monitor does not receive the response within the specified hard real-time interval, the external monitor issues a notification and/or shuts down at least part of the system or application.