Certificateless Encryption -- A Brief Introduction to Certificateless Encryption Schemes and Their Infrastructures -- Certificates and Revocation -- A Computational Framework for Certificate Policy Operations -- Resource Management with X.509 Inter-domain Authorization Certificates (InterAC) -- Reducing the Cost of Certificate Revocation: A Case Study -- Cryptographic Protocols -- Automatic Generation of Sigma-Protocols -- A Secure and Efficient Authenticated Diffie–Hellman Protocol -- Key Management for Large-Scale Distributed Storage Systems -- PKI in Practice -- Nationwide PKI Testing – Ensuring Interoperability of OCSP Server and Client Implementations Early during Component Tests -- On Device Identity Establishment and Verification -- ABUSE: PKI for Real-World Email Trust -- Encryption and Auctions -- Public-Key Encryption with Registered Keyword Search -- Practicalization of a Range Test and Its Application to E-Auction -- Timed-Ephemerizer: Make Assured Data Appear and Disappear -- Reputation and User Aspects -- Privacy and Liveliness for Reputation Systems -- A Multidimensional Reputation Scheme for Identity Federations -- On the Usability of User Interfaces for Secure Website Authentication in Browsers -- Digital Signatures -- Validity Models of Electronic Signatures and Their Enforcement in Practice -- Biometric Identity Based Signature Revisited -- How to Construct Identity-Based Signatures without the Key Escrow Problem.

This book constitutes the refereed post-conference proceedings of the 6th European Workshop on Public Key Services, Applications and Infrastructures, EuroPKI 2009, held in Pisa, Italy, in September 2009. The 18 revised full papers presented together with an invited speech were carefully reviewed and selected from 40 submissions. The papers are organized in topical sections on certificate less encryption, certificates and revocation, cryptographic protocols, PKI in practice, encryption and auctions, reputation and user aspects, and digital signatures.