This book constitutes the thoroughly refereed post-proceedings of the 12th International Workshop on Security Protocols, April 2004. The book presents 21 revised full papers presented together with edited transcriptions of some of the discussions following the presentations. Among the topics addressed are authentication, anonymity, verification of cryptographic protocols, mobile ad-hoc network security, denial of service, SPKI, access control, timing attacks, API security, biometrics for security, and others.

Introduction: Authentic Privacy.- Limits to Anonymity When Using Credentials.- Limits to Anonymity When Using Credentials (Transcript of Discussion).- A Cryptographic Framework for the Controlled Release of Certified Data.- A Cryptographic Framework for the Controlled Release of Certified Data (Transcript of Discussion).- One User, Many Hats; and, Sometimes, No Hat: Towards a Secure Yet Usable PDA.- One User, Many Hats; and Sometimes, No Hat (Transcript of Discussion).- Authentication Components: Engineering Experiences and Guidelines.- Authentication Components: Engineering Experiences and Guidelines (Transcript of Discussion).- Accountable Privacy.- Accountable Privacy (Transcript of Discussion).- Toward a Broader View of Security Protocols.- Toward a Broader View of Security Protocols (Transcript of Discussion).- Privacy, Control and Internet Mobility.- Privacy, Control and Internet Mobility (Transcript of Discussion).- Controlling Who Tracks Me.- Controlling Who Tracks Me (Transcript of Discussion).- BLIND: A Complete Identity Protection Framework for End-Points.- BLIND: A Complete Identity Protection Framework for End-Points (Transcript of Discussion).- Privacy Is Linking Permission to Purpose.- Privacy is Linking Permission to Purpose (Transcript of Discussion).- Establishing Trust with Privacy.- Establishing Trust with Privacy (Transcript of Discussion).- Safe and Private Data Sharing with Turtle: Friends Team-Up and Beat the System.- Safe and Private Data Sharing with Turtle: Friends Team-Up and Beat the System (Transcript of Discussion).- The Dancing Bear: A New Way of Composing Ciphers.- The Dancing Bear: A New Way of Composing Ciphers (Transcript of Discussion).- Identity and Location.- Identity and Location (Transcript of Discussion).- Security of Emergent Properties in Ad-Hoc Networks (Transcript of Discussion).- Pseudonymity in the Light of Evidence-Based Trust.- Pseudonymity in the Light of Evidence-Based Trust (Transcript of Discussion).- Secure Processor Consistent with Both Foreign Software Protection and User Privacy Protection.- Secure Processor Consistent with Both Foreign Software Protection and User Privacy Protection (Transcript of Discussion).- Why Are We Authenticating (Transcript of Discussion).- Anonymous Authentication.- Anonymous Authentication (Transcript of Discussion).- Towards a Mechanism for Discretionary Overriding of Access Control.- Towards a Mechanism for Discretionary Overriding of Access Control (Transcript of Discussion).- Last Orders.