64-bit-capable processors & Windows x64 & Virtualization

Source

• How do 64-bit instructions help with security?

64-bit-capable processors have the ability to run the 64-bit versions of Microsoft's substantially more secure XP, Windows 2003, and Vista operating systems. Those operating systems are more secure because Microsoft, having learned many lessons from mistakes in the past, made the firm decision to lock-down their 64-bit OS kernels. The 64-bit Windows kernels actively police themselves to guard against many rootkit-style and other kernel attacks that have caused so many problems for users of the 32-bit Windows operating systems. 

These advanced kernel-protection technologies cannot be ported back into current or even future versions of Microsoft's 32-bit operating systems because doing so would “break” so many existing programs and drivers as to make the system impossible to use. Microsoft knows that one day the personal computing industry will have moved over to 64-bit operating systems much as we all once moved from the 16-bit based systems to 32-bits. 

SecurAble indicates by displaying either a “32” or a “64” whether the system's processor has the 64-bit instructions or extensions necessary to run 64-bit versions of Microsoft's present and future operating systems.

• How does Hardware DEP help with security?

As was mentioned in the boxes above, hardware support for DEP is the single most exciting and potentially powerful technology for detecting, blocking, and preventing all manner of exploitation of “unchecked buffer” buffer overruns in Windows. Hardware-enforced DEP is the malicious hacker's worst nightmare since it has the potential to catch and stop nearly all Internet-style remote communications buffer overflow attacks.

• How does Hardware Virtualization help with security?

“Virtual Machine” technology is used to create fully contained environments that can be used to insulate the real hosting operating system from any actions taken by software running within the “virtual” environment. Although this security benefiting virtual machine technology has been used for many years, its widespread adoption has been slowed down by the significant performance overhead imposed by software emulation of the virtual environment. Intel's and AMD's native hardware support for virtual machines means that virtually all of this emulation overhead can be eliminated from both the host and virtual environments. This makes the use of virtual machines for security containment much more practical.

The second benefit of hardware support is that even malicious software running with maximum privileges in the system's kernel is unable to escape from virtual containment. Thus, hardware support for virtual machine technology introduces the possibility of creating a “hypervisor” to operate at a hardware-enforced level below the operating system “supervisor” which opens many exciting possibilities for further enhancing the system's security. It will likely be several years before these capabilities are offered natively within Windows, but we might expect to see third-party security software publishers taking advantage of these features in the near future.