Invited Talk -- ECRYPT: The Cryptographic Research Challenges for the Next Decade -- Reduction of Security/Primitives -- Relationships Between Diffie-Hellman and “Index Oracles” -- On the Security Notions for Public-Key Encryption Schemes -- Efficient Unconditional Oblivious Transfer from Almost Any Noisy Channel -- Signature Schemes -- A Provably Secure Short Transitive Signature Scheme from Bilinear Group Pairs -- Group Signatures with Separate and Distributed Authorities -- Threshold Cryptography in Mobile Ad Hoc Networks -- Anonymity and Privacy -- Designated Verifier Signatures: Anonymity and Efficient Construction from Any Bilinear Map -- Group Signatures: Better Efficiency and New Theoretical Aspects -- Efficient Blind Signatures Without Random Oracles -- Authentication and Identification -- Minimalist Cryptography for Low-Cost RFID Tags (Extended Abstract) -- On the Key Exposure Problem in Chameleon Hashes -- Zero Knowledge -- Identity-Based Zero-Knowledge -- Public Key Cryptosystems -- A Robust Multisignature Scheme with Applications to Acknowledgement Aggregation -- Efficient Key Encapsulation to Multiple Parties -- Improved Signcryption from q-Diffie-Hellman Problems -- Distributed Cryptography -- Colored Visual Cryptography Without Color Darkening -- On the Size of Monotone Span Programs -- Universally Composable DKG with Linear Number of Exponentiations -- Cryptanalysis of Public Key Cryptosystems -- An Algebraic Approach to NTRU (q = 2 n ) via Witt Vectors and Overdetermined Systems of Nonlinear Equations -- Efficient Cryptanalysis of RSE(2)PKC and RSSE(2)PKC -- Cryptanalysis -- The Decimated Sample Based Improved Algebraic Attacks on the Nonlinear Filters -- Non-randomness of the Full 4 and 5-Pass HAVAL -- Email Security -- Controlling Spam by Secure Internet Content Selection -- Key Distribution and Feedback Shift Registers -- On Session Identifiers in Provably Secure Protocols -- How to Embed Short Cycles into Large Nonlinear Feedback-Shift Registers.

This book constitutes the thoroughly refereed postproceedings of the 4th International Conference on Security in Communication Networks, SCN 2004, held in Amalfi, Italy in September 2004. The 25 revised full papers presented together with an invited paper were carefully selected during two rounds of reviewing and improvement. The papers are organized in topical sections on reduction of security and primitives, digital signature schemes, anonymity and privacy, authentication and identification, zero knowledge, public key cryptosystems, distributed cryptography, cryptanalysis of public key crypto systems, cryptanalysis, email security, and key distribution and feedback shift registers.