What is kernel rings in a system ? | kernel protection ring | cloudpradeep
What is Kernel rings ?
Kernel ring or Formally known as Linux Protection ring, it helps to stay secure from other source of access. In order to protect from other domain or providing protection to operating system kernel uses some permission levels and that protection levels is known as Kernel Rings or protection ring .
Why Kernel rings are used ?
The main advantages of Kernel protection ring is, it helps to protect the against the system crashes. It helps to protect your system from unwanted or malicious behaviour. It has direct access to CPU and Ram so if a process running in the outer ring crashes, it can be restarted without losing data.
There are basically 4 levels of permission or privileged ranging from 0 to 3. In which the most privileged ring is Ring 0 where the low privilege ring is Ring 3.
Ring 0 :-
· The Ring 0 is nearby to the kernel . Which is core of the operating system and that can access most of everything in a system. All the system processes are running in this kernel mode so if anything will fails here then entire operating system will shutdown. So to prevent this types of problem Ring 0 has most permission.
Ring 1 and 2 :-
· The ring 1 and 2 is having nearly same permission level so this 2 Ring are called Device Driver Ring . Where the ring 1 is used to interact with the hardware of your computer like playing music through speaker displaying video on monitor etc. .
· The Ring 2 is used to do mainly input and output permission like saving something to storage loading etc. . It need to interact with system storage to perform this action.
Ring 3 :-
· The Ring 3 is called User mode or Application mode. Because in this layer a user interact with the computer by using so Application so it is called like this. The example of this layer is Viewing and Editing the Document like creating a Word document.
That’s a simple thing about kernel mode or you can say kernel protection ring . i hope you will got your answer.