History of Cryptography.- The Contribution of E.B. Fleissner and A. Figl for Today's Cryptography.- On the history of cryptography during WW2, and possible new directions for cryptographic research.- Public Key Cryptography.- Efficient Factoring Based on Partial Information.- A Public-Key Cryptosystem Based on Shift Register Sequences.- A Comment on Niederreiter's Public Key Cryptosystem.- Implementation Study of Public Key Cryptographic Protection in an Existing Electronic Mail and Document Handling System.- Cryptanalysis of the Dickson-Scheme.- Simultaneous Security of Bits in the Discrete Log.- On Public-Key Cryptosystems Built Using Polynomial Rings.- Secret Key Cryptography.- Is the Data Encryption Standard a Group? (Preliminary Abstract).- Two New Secret Key Cryptosystems.- Cryptanalysts Representation of Nonlinearly Filtered ML-Sequences.- Authorized Writing for "Write-Once" Memories.- Shiftregister Sequences and Related Topics.- On Functions of Linear Shift Register Sequences.- On Feedforward Transforms and p-Fold Periodic p-Arrays.- Generalized Multiplexed Sequences.- A Note on Sequences Generated by Clock Controlled Shift Registers.- Using Algorithms as Keys in Stream Ciphers.- On the Linear Complexity of Combined Shift Register Sequences.- Analysis of a Nonlinear Feedforward Logic for Binary Sequence Generators.- Linear Complexity and Random Sequences.- Cryptographic Systems and Applications.- Engineering Secure Information Systems.- The Chipcard - An Identification Card with Cryptographic Protection.- Encryption Needs, Requirements and Solutions in Banking Networks.- The Role of Encipherment Services in Distributed Systems.- Modeling of Encryption Techniques for Secrecy and Privacy in Multi-User Networks.- Full Encryption in a Personal ComputerSystem.- Showing Credentials Without Identification.- Networks Without User Observability - Design Options.- The Verifiability of Two-Party Protocols.- The Practice of Authentication.- Message Protection by Spread Spectrum Modulation in a Packet Voice Radio Link.