What do the terms "authentication" and "authorization" mean in network security?

In network security, "authentication" and "authorization" represent two distinct but interconnected concepts essential for maintaining secure access to systems and resources.

Authentication is the process that verifies the identity of a user or device. It ensures that the individual trying to gain access is indeed who they claim to be. This verification can involve various methods, such as passwords, biometric scans, or tokens. The goal is to establish confidence that the user is genuine before allowing them access to sensitive information or systems.

On the other hand, authorization occurs after successful authentication. Once a user's identity has been confirmed, authorization determines what resources or actions the authenticated user is allowed to access or perform. This can involve setting permissions based on roles, such as allowing specific users to edit files while others can only view them. Authorization ensures that users only have access to the information and functionalities necessary for their roles, thereby applying a principle of least privilege to enhance security.

Understanding the difference between these two terms is crucial for designing secure systems. Authentication ensures a trustworthy identity, while authorization governs access rights, thus forming a comprehensive security framework.