Authentication

In computer security, authentication is the process of attempting to verify the digital identity of the sender of a communication such as a request to log in.

The sender being authenticated, often referred to as the principal, may be a person using a computer, a computer itself or a computer program.

A blind credential, in contrast, does not establish identity at all, but only a narrow right or status of the user or program.

In a web of trust, "authentication" is a way to ensure users are who they say they are—that the user who attempts to perform functions in a system is in fact the user who is authorized to do so.

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