Which term refers to the verification of identity with respect to legitimate user access?

Authentication refers to the process of verifying the identity of a user, system, or entity. It is a critical aspect of security in information systems, ensuring that individuals or systems requesting access are indeed who they claim to be. By implementing authentication measures—such as passwords, biometric scans, or security tokens—organizations can mitigate the risk of unauthorized access to their systems and resources.

In contrast, identification involves recognizing a user or system, typically through a username or ID, but does not confirm whether the entity is legitimate. Validation is about ensuring that data is correct and conforms to established rules before it can be used or processed. Authorization follows authentication and deals with what an authenticated user is permitted to do—defining levels of access but not confirming identity. Thus, authentication is specifically about confirming the identity of users prior to granting them access to systems.