Cryptologists like to talk about a familiar pantheon of characters in their cryptographic dramas. This tutorial will discuss these folks a bit; if you read past this tutorial, Alice and Bob and their friends (or enemies) will become your close acquaintances. Say hello to our friends! (They often go by their initials in cryptologists' shorthand).

From The Jargon File: Bruce Schneier's definitive introductory text Applied Cryptography (2nd ed., 1996, John Wiley & Sons, ISBN 0-471-11709-9) introduces a table of dramatis personae headed by Alice and Bob. Others include Carol (a participant in three- and four-party protocols), Dave (a participant in four-party protocols), Eve (an eavesdropper), Mallory (a malicious active attacker), Trent (a trusted arbitrator), Walter (a warden), Peggy (a prover), and Victor (a verifier). These names for roles are either already standard or, because of the wide popularity of the book, may quickly become so.