Apparatus and method for creating a trusted environment

A computer apparatus for creating a trusted environment comprising:

• a trusted device arranged to acquire a first integrity metric to allow determination as to whether the computer apparatus is operating in a trusted manner, said trusted device being a physical device which binds an identity of the computer apparatus to first reliably measured data by means of said first integrity metric, wherein the trusted device is a tamper resistant device;
• a software trust routine which binds an identity of at least an operating system environment to second reliably measured data by means of at least a second integrity metric;
• a processor arranged to allow execution of the trust routine and associated operating environment, and means for restricting access of the operating system environment to resources available to the trust routine, wherein the trust routine is arranged to acquire (i) the first integrity metric of said trusted device as an indicator of whether a user of said computer apparatus should trust that said computer apparatus and (ii) a second integrity metric to allow determination as to whether the operating system environment is operating in a trusted manner consistently with said second reliably measured data;
• wherein the means for restricting access of the operating environment comprises a control layer of software and an operating system of the operating system environment adapted such that any instructions in the operating system of the operating system environment with potential to affect any environment outside the operating system environment cause a transition to a control layer.