Enhancing the security of block ciphers with the aid of parallel substitution box construction

P. Nastou1, Y.C. Stamatiou2
1Atmel Hellas S.A., Athens, Greece
2Department of Computer Engineering and Informatics, University of Patras, Patras, Greece

Tóm tắt

When considering block cipher designs, one feature that is seemingly not related to their robustness of a design is algorithmic variability, i.e. the ability to effect changes on a design that essentially leave its structure unchanged while they modify its functional characteristics. This feature, however, is related to robustness as there are situations where a specific algorithm is either suspected to be under cryptanalytic attack or it is not considered secure any more due to a discovered weakness. The easiest action would be to change the characteristics of the algorithm in a way that obscures the cryptanalytic attack or that eliminates the cipher's weaknesses. Our focus is on this kind of changes, using as a specific case the CAST-128 cipher The changes we consider refer to the algorithm's substitution boxes and since the creation of good substitution boxes is a highly time consuming process, we also provide a parallel algorithm for completing this task quickly.

Từ khóa

#Cryptography #Concurrent computing #Algorithm design and analysis #Parallel algorithms #Distributed computing #Design engineering #Electronic mail #Robustness #Field programmable gate arrays #Computer security

Tài liệu tham khảo

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