| Failure to a known safe state helps prevent systems from failing to a state that may cause loss of data or unauthorized access to system resources. Network elements that fail suddenly and with no incorporated failure state planning may leave the hosting system available but with a reduced security protection capability. Preserving information system state information also facilitates system restart and return to the operational mode of the organization with less disruption to mission-essential processes.
If the router fails in an unsecure manner (open), unauthorized traffic originating externally to the enclave may enter, or the device may permit unauthorized information release. Fail secure is a condition achieved by employing information system mechanisms to ensure, in the event of a device initialization failure, device shutdown failure, or an abort failure of the router, it does not enter into an unsecure state where intended security properties no longer hold.
If the device fails, it must not fail in a manner that will allow unauthorized access. If the router fails for any reason, it must stop forwarding traffic altogether or maintain the configured security policies. If the device stops forwarding traffic, maintaining network availability would be achieved through device redundancy.
Since it is usually not possible to test this capability in a production environment, systems should either be validated in a testing environment or prior to installation. This requirement is usually a function of the design of the router component. Compliance can be verified by acceptance/validation processes or vendor attestation. |
