Kerberos
Kerberos authentication offers a proven, non-proprietary solution for maximizing the security of virtually any computing system without compromising performance. This is the first authoritative, accessible guide to Kerberos for both users and administrators. Authored by Brian Tung, who wrote the Internet`s #1 Kerberos web site, this book brings together everything you need to understand, deploy, use, and manage Kerberos servers. Tung presents a remarkably clear explanation of Kerberos components, algorithms, and protocols, plus a full chapter on developing Kerberized applications. Finally, preview the exciting future of Kerberos, including integration with public-key cryptography, smart cards, and Windows 2000.

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The authentication system of MIT's Project Athena. It is based on symmetric key cryptography. Adopted by OSF as the basis of security for DME.