Human Interactive Proofs: Second International Workshop, HIP 2005, Bethlehem, PA, USA, May 19-20, 2005, Proceedings

E-commerce services are su?ering abuse by programs (bots, spiders, etc.) m- querading as legitimate human users. E?orts to defend against such attacks have, over the past several years, stimulated investigations into a new family of security protocols - "Human Interactive Proofs" (HIPs) - which allow a person to authenticate herself as a member of a given group: e.g., as a human (vs. a machine), as herself (vs. anyoneelse), as an adult (vs. a child). Most commercial usesofHIPstodayareCAPTCH...