Application Support
Kernel and User Mode Enhancements
- To provide better application isolation
- Microsoft architects have redesigned the security levels for core components of the operating system
- Kernel mode access
- Has total access to all of data and hardware.
- If a kernel mode component performs a bad operation that crashes the computer, there is little the operating system can do to stop it or recover. The phrase "blue screen of death" (BSOD) came to describe the error screen displayed by the operating system when it realized that a component has performed an action that is considered bad enough to force the operating system to halt.
- User mode access has access to its own private space and nothing else
- Redesigned kernel supports more types of software running at a user level instead of a kernel level
- Ring level describes security levels at the CPU hardware level from Ring 0 (least restricted) to 3 (most restricted).