  Cloud computing relies on secure and efficient virtualization. Software level
security solutions compromise the performance of virtual machines (VMs), as a
large amount of computational power would be utilized for running the security
modules. Moreover, software solutions are only as secure as the level that they
work on. For example a security module on a hypervisor cannot provide security
in the presence of an infected hypervisor. It is a challenge for virtualization
technology architects to enhance the security of VMs without degrading their
performance. Currently available server machines are not fully equipped to
support a secure VM environment without compromising on performance. A few
hardware modifications have been introduced by manufactures like Intel and AMD
to provide a secure VM environment with low performance degradation. In this
paper we propose a novel memory architecture model named \textit{ Architectural
Support for Memory Isolation(ASMI)}, that can achieve a true isolated physical
memory region to each VM without degrading performance. Along with true memory
isolation, ASMI is designed to provide lower memory access times, better
utilization of available memory, support for DMA isolation and support for
platform independence for users of VMs.

Hardware Architecture