Machine Virtualisation, Virtual Machines, and TPMs

This chapter provides some background to the concept of trusted virtualisation because, while virtualisation is not essential when implementing a trusted platform, the authors anticipate that it will become the dominant implementation of Trusted Computing in PCs, if nothing else. The main benefit of virtualisation for Trusted Computing is that it can provide process isolation. This is critical for security because one must be able to prevent a rogue software process from interfering with another software process. Trusted virtualisation depends on a hypervisor running as the lowest layer (most privileged layer) of software. The hypervisor can both use the TPM to protect the hypervisor, and use the TPM to help protect the platform.