What is Difference Between Authentication and Authorization ?

Authentication and Authorization are two terms that are often used interchangeably in the tech world. However, both these terms are quite different with entirely different concepts and meanings.

Authentication

Simple English Meaning: The process or action of verifying the identity of a user or process.

Authentication is the process of proving one’s identity before gaining access to a resource. We see Authentication everywhere in our day to day lives, such as:

1. Passports
2. ID Cards
3. Aadhaar Cards

In Tech World, we see Authentication in the following scenarios:

1. Website LogIns
2. Mobile Phone LogIns
3. Computer LogIns

Generally, Authenticating yourself is just proving to the system that you are the one you are claiming to be. It normally takes place in the following way:

A user tries to Log In to the system and is asked to present his username and password. When both of these things are entered and are validated as true by the system, the user is authenticated and is allowed to Log In.

Types of Authentication

1. Single-Factor Authentication: It is the simplest form of Authentication and requires just a username and password. Once these two are validated, a user is allowed to log in. Example: Simple website login
2. Two-Factor Authentication: This form of Authentication requires an additional piece of information only the user knows, along with the username and password. Example: Logging In to a website with the username and password and an OTP (One-Time Password) sent to the user’s email id or phone.
3. Multi-Factor Authentication: This is the most advanced method of Authentication, which requires two or more levels of security from independent categories of authentication to grant a user access to the system. This form of authentication utilizes factors that are independent of each other to eliminate any data exposure.

Authorization

Simple English Meaning: Official permission for something to happen or the act of giving someone official permission.

Authorization is the process of providing or granting users permission to access a protected resource.

Some examples of
Authorisation are:

1. Granting individual access to a specific location in a building
2. Allowing a user to access specific parts of a website

etc.

Authentication and Authorization Working Together in Real World

Let us take a real-world example where we see both Authentication and Authorization concepts working together.

In offices, when
a new employee joins, he is given two things-

1. ID card (Authentication)
2. Access Card (Authorization)

The use of the ID
Card is to prove the employee’s identity. It contains the name, employee ID and
some other details of the employee.

The use of the Access Card is to grant special permissions to an employee to access specific parts of the office. For example, some employees might not have permission to access the server room and some employees might have. The Access Card helps in establishing the relationship between a user and the scope of access he has.

Also Read: What is OAuth 2.0 ? How it Works ? A Detailed Explanation of Authorization Framework