Network Security: Private Communications in a Public World, 3rd Edition

9 Authentication of People

Humans are incapable of storing high-quality cryptographic keys and they have unacceptable speed and accuracy when performing cryptographic operations. They are also large, expensive to maintain, difficult to manage, and they pollute the environment. It is astonishing that these devices continue to be manufactured and deployed, but they are sufficiently pervasive that we must design our systems around their limitations.

—Radia Perlman

Authentication is the process of reliably verifying the identity of someone (or something). There are lots of examples of authentication in human interaction. People who know you can recognize you based on your appearance or voice. A guard might authenticate you by comparing you with ...