We propose a variational quantum attack algorithm (VQAA) for classical advanced encryption standard (AES)-like symmetric cryptography, as exemplified by the simplified-data (S-DES). In VQAA, known ciphertext is encoded ground state of Hamiltonian that constructed through regular graph, and can be found using approach. designed ansatz cost function S-DES’s attack. It surprising sometimes VQAA ev...

The ever-increasing need for securing computing systems using cryptographic algorithms is spurring interest in the efficient implementation of common algorithms. While can be implemented software base instruction sets, there considerable potential to reduce memory cost and improve speed specialized instructions associated hardware. However, a assess benefits costs implementations new that imple...

In this lecture, we give an overview to the public-key cryptography, which is also referred to as asymmetric cryptography. We will first introduce the background of public-key cryptography. Then we will study the model of public-key cryptosystem, and the requirement to design a practical public-key algorithm. Finally, we will study the design of RSA algorithm. The concept of public-key (asymmet...

Robust authenticated encryption (RAE) is a primitive for symmetric encryption that allows to flexibly specify the ciphertext expansion, i.e., how much longer the ciphertext is compared to the plaintext. For every ciphertext expansion, RAE aims at providing the best-possible authenticity and confidentiality. To investigate whether this is actually achieved, we characterize exactly the guarantees...

Quantum cryptography is commonly used to generate fresh secure keys with quantum signal transmission for instant use between two parties. However, research shows that the relatively low key generation rate hinders its practical use where a symmetric cryptography component consumes the shared key. That is, the security of the symmetric cryptography demands frequent rate of key updates, which lea...

In this paper we show how to use an old mathematical concept of diophantine analysis, the approximation theorem of Kronecker, in symmetric cryptography. As a first practical application we propose and analyze the new symmetric 128-bit block cipher KronCrypt. The cipher is a 4-round Feistel network with a non-bijective round function f made up of a variable number of large key-dependent S-boxes,...