# On the Use of Interconnection Networks in Cryptography

## Abstract

Cryptosystems can be viewed as sets of permutations from which one permutation is chosen as cryptofunction by specifying a key. Interconnection networks have been widely studied in the field of parallel processing. They have one property that makes them very interesting for cryptology, i.e. they give the opportunity to access and perform permutations at the same time. This paper presents two examples of how cryptology can benefit from the use of interconnection networks. One is a new construction of a pseudo-random permutation (generator) from one single pseudo-random function (generator). The search for such constructions has been of major interest since Luby and Rackoff gave the first construction in 1986. The second example presents a cryptosystem based on interconnection networks and a certain class of boolean functions. Some arguments for its security are given. Although there is a relation between the two examples they complement each other in using different properties of interconnection networks. This can be regarded as an argument that exploiting the full potential of interconnection networks can establish completely new techniques in cryptology.

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