Charlie Kaufman works for Microsoft in the Windows Core Architecture group designing security enhancements in the areas of authentication, authorization, integrity protection, network security, system management, and user interfaces. He is co-author of the book "Network Security: Private Communication in a Public World" (Prentice Hall, 2002). He served on the National Academy of Sciences expert panel whose members wrote the book "Trust in Cyberspace". He has contributed to a number of IETF standards efforts including IPsec and S/MIME, and served as a member of the Internet Architecture Board (IAB). He was previously a Distinguished Engineer at IBM, where he was Chief Security Architect for Lotus Notes and Domino. He holds over 30 patents in the fields of computer security and computer networking.