Taming Virtualization

Although the term virtualization has been around for decades, only recently has it become a buzzword in the computer systems community with the revival of virtual machines (VMs), driven by efforts in industry and academia. VMs are software entities that emulate a real machine´s functionality; they execute under the control of a hypervisor that virtualizes and multiplexes low-level hardware resources. Hypervisors come in two flavors: non-hosted, which run directly on top of the hardware, and hosted, which are integrated with a host operating system (OS). The presence of a hypervisor makes VMs subject to a level of visibility and control that´s hard to achieve with real machines. The small size, isolation, and mediation power of an ideal hypervisor over VMs make it an interesting candidate for a trusted computing base, with applications in security research fields such as intrusion detection, integrity protection, and malware analysis, among others.