5.1 Explain the function and purpose of authentication services

Authentication is the mechanism by which a person proves their identity to a system. It is the process of proving that a subject is the valid user of an account. Often, the authentication process involves a simple username and password. But other more complex authentication factors or credential-protection mechanisms are involved in order to provide strong protection for the logon and account-verification process. The authentication process requires that the subject provide an identity and then proof of that identity.


Remote Authentication Dial-In User Service (RADIUS) is a centralized authentication system. It’s often deployed to provide an additional layer of security for ...

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