Abstract
Every new OS needs to support legacy software. Virtualization is one technique to solve this problem. Unfortunately virtualization can have a negative impact on the security of an application, as it adds a new layer of indirection to the TCB. In this talk I will present Vancouver on Nova, a VMM on a thin hypervisor, that allows to run unmodified OSes. Due to careful design and the now widely available hardware support for virtualization we can achieve a TCB which is approximately an order of magnitude smaller than comparable solutions.