Authentication and authorization are two distinct concepts in computer security that are often used together to control access to resources. Although they are related, they serve different purposes.
Authentication refers to the process of verifying the identity of a user or a system. This process is used to ensure that the person or entity accessing a resource is who they claim to be. Authentication can be achieved through a variety of methods, such as passwords, biometric scans, smart cards, or public key certificates.
Authorization, on the other hand, is the process of granting or denying access to a resource or system based on the user’s or system’s identity and the permissions associated with that identity. Authorization checks whether a user or a system has the right to access a particular resource, and what level of access they have. Authorization is typically implemented through the use of access control lists (ACLs) or other security policies.
To summarize, authentication is the process of verifying the identity of a user or a system, while authorization is the process of granting or denying access based on that identity. In other words, authentication ensures that you are who you say you are, while authorization determines what you are allowed to do based on your identity.