Skip to main content

Protection [Operating System]

By
Protection is the mechanisms & policies to keep programs & users from accessing or changing stuff they not do. It is internal to OS.
Protection refers to a mechanism for controlling the access of programs, processes or users to the resources defined by a computer system.
Protection ensures that only processes that have gained proper authorization from OS can operate on the files, memory segments, CPU & other resources of a system.

Goals of Protection
The OS consists of a collection of objects (hardware or software). Each object has a unique name & can be accessed through a well defined set of operations. The goal is to ensure that each object is accessed correctly & only by those processes that are allowed to do so.
The guiding principles of Protection are as follow:
1. Principle of least privilege Programs, users & systems should be given just enough privileges to perform their task so that they can’t alter or harm. 2. Separate “Policy” from “Mechanism” Mechanism: The stuff built into the OS to make Protection work. Policy: The data that says who can do what to whom.  
Labels:

Comments

Post a Comment

Popular posts from this blog

Object Oriented Programming

By
Object Oriented Programming Programming paradigm that represents the concept of "objects" that have data fields (attributes that describe the object) and associated procedures known as methods Programming methodology based on objects, instead of just functions and procedures Focuses on data rather than process As individual objects can be modified without affecting other aspects of the program, it is easier for programmers to structure and organize software programs Easier to update and change programs written in object-oriented languages Simula was the first object oriented programming language Eg: C++, Java, etc. Features of OOPS Objects Referred as instance of class Basic run-time entities in an object-oriented system a person, a place, a bank account, a table of data, etc can be an object They occupy space in memory that keeps its state  Each object contains data and code to manipulate the data  Classes Blue print or prototype  which defi
Post a Comment
Read more

How structure elements are stored?

By
  The elements of a structure are always stored in contiguous memory locations. This can be illustrated as void main() {     struct student      {      int roll;      float marks;      char remarks;   };   struct student st={200,60.5,'P'};   printf("\nAddress of roll=%u",&st.roll);   printf("\nAddress of marks=%u",&st.marks);   printf("\nAddress of remarks=%u",&st.remarks);   getch(); } Output: Address of roll=65518 Address of marks=65520 Address of remarks=65524                  st.roll               st.marks                          st.remarks 200 60.5 ‘P’               65518             65520                               65524           
Post a Comment
Read more

How containership is different than inheritance ?

By
               Inheritance is the mechanism of deriving properties of one class into another. While containership is mechanism in which one class contain objects of other classes as its member.                     class alpha{_ _ _ _ _ };                     class beta{_ _ _ _ _ };                      class gamma                      {                         alpha a;                         beta b;                       _ _ _ _ _ };            All objects of gamma class will contain the objects a and b, this kind of relationship is called containership or nesting.
Post a Comment
Read more