What is the difference between authentication and authorization?


Authentication and authorization are two distinct but closely related concepts in the field of information security. Here are five key differences between authentication and authorization:

Definition:

Authentication: Involves the process of verifying the identity of a user, system, or device. It ensures that the entity claiming to be a particular user is, in fact, that user. Authentication mechanisms include passwords, biometrics, smart cards, and multi-factor authentication.

Authorization: Refers to the process of granting or denying access to specific resources or actions based on the authenticated user’s privileges. Once a user’s identity is verified through authentication, authorization determines what actions or resources that user is allowed to access.

Purpose:

Authentication: Establishes the identity of a user or system. It answers the question, “Who are you?” and ensures that the entity trying to access a system is the one it claims to be.

Authorization: Determines the permissions and privileges associated with a verified identity. It answers the question, “What are you allowed to do?” and controls access to specific resources or functionalities based on the user’s role or permissions.

Focus:

Authentication: Focuses on verifying the identity of an entity through the presentation of credentials or evidence. It ensures that the entity is genuine and not an imposter.

Authorization: Focuses on determining the rights and permissions of an authenticated entity. Once the identity is established, authorization defines what actions the entity is allowed to perform.

Process Timing:

Authentication: Typically occurs before authorization. Users must be authenticated before the system can make decisions about what actions or resources they are allowed to access.

Authorization: Follows authentication in the access control process. After verifying the identity of a user, the system checks the user’s permissions to determine whether the requested actions or resources are allowed.

Example:

Authentication: Verifying a user’s identity by entering a username and password, providing a fingerprint, or using a security token.

Authorization: Determining whether a user with a verified identity (after authentication) is allowed to access a specific file, modify a database, or perform other actions based on their assigned roles and permissions.

In summary, authentication focuses on verifying the identity of a user, system, or device, while authorization determines what actions or resources an authenticated entity is allowed to access. Authentication precedes authorization in the access control process, and both are essential components of a comprehensive security strategy.