Ring 2

In computer architecture, Ring 2 is a privilege level in the x86 processor architecture's protection ring model. This model provides hardware-enforced privilege separation, allowing the operating system to define different levels of access to system resources.

Ring 2 is one of the inner rings, indicating a higher level of privilege than Ring 3 but less than Ring 1 and Ring 0. Software running in Ring 2 has more direct access to hardware and system resources compared to software running in Ring 3, often user-level applications. However, it is still restricted in comparison to Ring 1 and Ring 0, which are typically reserved for critical operating system components.

Historically, Ring 2 was intended for use with device drivers and other system-level services. However, in modern operating systems like Windows and Linux, Ring 2 is rarely used directly. Most device drivers operate in Ring 0, the highest privilege level, or in user space with the assistance of kernel-level services. The lack of utilization stems from complexities in managing and securing code running in Ring 2 and the development of alternative techniques for device driver management. The unused nature helps improve security, as a successful attack on Ring 3 would still face further barriers before reaching the kernel (Ring 0).