The advancement in the field of technology and science has rendered the classical algorithms used for securing data vulnerable to attacks by quantum computers. Post quantum cryptography aims at establishing quantum safe algorithms so that data can be secured. Advanced Encryption Standard (AES) is a symmetric key block cipher which provides security against known quantum attacks. The Shor’s and Grover’s algorithms are the quantum algorithms which have proved to break encryption provided by security mechanisms like RSA and even have the potential to break AES-128 in future. However, if key size of symmetric key security mechanisms is increased then security provided by them cannot be broken by both classical and quantum computers in near future. Quantum computers are becoming more and more prevalent, but there is still some concern about their security. In this paper, we will show that the current quantum computers in use cannot break AES-256 encryption with Grover’s algorithm. We have implemented AES-256 for encryption of files in our system and proposed a proof that the qubits used by quantum computers are not enough to break AES-256 with Grover’s algorithm. We believe that this provides strong evidence that current quantum computers are not a threat to encrypted data using AES-256. We hope this will ease concerns about using quantum computing for secure applications and encourage further development of these powerful machines.
Privacy of information can be maintained using two cryptographic techniques i.e. symmetric key cryptography and asymmetric key cryptography. For securing data using symmetric key cryptography, Advanced Encryption Standard (AES) is one of the trusted cryptographic algorithms. AES is a block cipher based symmetric key cryptographic algorithm which can resist conventional computers as well as quantum computers. In recent years, many researches have been done that exploit the property of quantum mechanics to solve mathematical problems that are ever difficult for conventional computers. Many of the cryptographic algorithms can be broken if large scale quantum computers are ever made. This paper depicts the proof of AES-256 using Grover’s algorithm which can resist quantum. Keywords: AES,RSA, ECC, Quantum Key Distribution (QKD), Quantum bit commitment, Quantum Cryptography.
Suppose some data have been encrypted, can you compute with the data without decrypting them? This problem has been studied as homomorphic encryption and blind computing. We consider this problem in the context of quantum information processing, and present the definitions of quantum homomorphic encryption (QHE) and quantum fully homomorphic encryption (QFHE). Then, based on quantum one-time pad (QOTP), we construct a symmetric QFHE scheme, where the evaluate algorithm depends on the secret key. This scheme permits any unitary transformation on any
n-qubit state that has been encrypted. Compared with classical homomorphic encryption, the QFHE scheme has perfect security. Finally, we also construct a QOTP-based symmetric QHE scheme, where the evaluate algorithm is independent of the secret key.