We experimentally demonstrate an all-optical binary counter composed of four semiconductor optical amplifier based all-optical switching gates. The time-of-flight optical circuit operates with bit-differential delays between the exclusive-OR gate used for modulo-2 binary addition and the AND gate used for binary carry detection. A movie of the counter operating in real time is presented.

This work is a study of DES-like ciphers where the bitwise exclusive-or (XOR) operation in the underlying Feistel network is replaced by an arbitrary group operation. We construct a two round simplified version of DES that contains all the DES components and show that its set of encryption permutations is not a group under functional composition, it is not a pure cipher and its set of encryptio...

In the present paper, we investigate the problem of constructing MDS matrices with as few bit XOR operations as possible. The key contribution of the present paper is constructing MDS matrices with entries in the set of m ×m non-singular matrices over F2 directly, and the linear transformations we used to construct MDS matrices are not assumed pairwise commutative. With this method, it is shown...

There are two major approaches to the synthesis of logic circuits. One is based on a predominantly algebraic factorization leading to AND/OR logic optimization. The other is based on classical Reed-Muller decompositionmethod and its related decision diagrams, which have been shown to be efficient for XOR-intensive arithmetic functions. Both approaches share the same characteristics: while one i...

In this paper we investigate the properties of self induced transparency (SIT) solitons, propagating in a Λ-type medium. We find that the interaction between SIT solitons can lead to trapping with their phase preserved in the ground state coherence of the medium. These phases can be altered in a systematic way by the application of appropriate light fields, such as additional SIT solitons. Furt...

Novel digital technologies always lead to high density and very low power consumption. One of these concepts is Quantum-dot Cellular Automata (QCA), which is one of the new emerging nanotechnology-based on Coulomb repulsion. This article presents three architectures of logical “XOR” gate, a novel structure of two inputs “XOR” gate, which is used as a module to implement four inputs “XOR” gate a...

New to neuroscience with implications for AI, the exclusive OR, or any other Boolean gate may be biologically accomplished within a single region where active dendrites merge. This is demonstrated below using dynamic circuit analysis. Medical knowledge aside, this observation points to the possibility of specially coated conductors to accomplish artificial dendrites.

The Bistable Ring (BR) Physical Unclonable Function (PUF) is a newly proposed hardware security primitive in the PUF family. In this work, we comprehensively evaluate its resilience against Machine Learning (ML) modeling attacks. Based on the success of ML attacks, we propose XOR strategies to enhance the security of BR PUFs. Our results show that the XOR BR PUF with more than four parallel BR ...

As unconventional computation matures and non-standard programming frameworks are demonstrated, the need for formal verification will become more prevalent. This is so because “programming” in unconventional substrates is difficult. In this paper we show how conventional verification tools can be used to verify unconventional programs implementing a logical XOR gate.

In this paper we analyse the role of some of the building blocks in SHA-256. We show that the disturbance correction strategy is applicable to the SHA-256 architecture and we prove that functions Σ, σ are vital for the security of SHA-256 by showing that for a variant without them it is possible to find collisions with complexity 2 64 hash operations. As a step towards an analysis of the full f...