Patent ID: 7574610

Claim:
A security device for use with a computer system comprising at least two execution environments, wherein a first execution environment includes a host operating system comprising a relatively lower assurance operating system and a second execution environment includes a guest operating system comprising a relatively higher assurance operating system, the guest operating system including one or more security functions, wherein the security device is configured to monitor an internal state of the computer system and to determine a state of the guest operating system, the security device comprising: a querier connected to said computer system and configured to request a status from said guest operating system of said computer system; and a user alerter connected to said querier, said user alerter configured to signal if an unsatisfactory state of said guest operating system is determined, wherein said unsatisfactory state is determined to exist when said guest operating system is not responsive, a response received from said guest operating system is discerned as not coming from said guest operating system, or a response received from said guest operating system indicates a security breach.