A Cryptography Engineer’s Perspective on Quantum Computing Timelines

My position on the urgency of rolling out quantum-resistant cryptography has changed compared to just a few months ago. You might have heard this privately from me in the past weeks, but it’s time to signal and justify this change of mind publicly. There had been rumors for a while of expected an...

The Manipulate-And-Observe Attack on Quantum Key Distribution

Quantum key distribution is often regarded as an unconditionally secure method to exchange a secret key by harnessing fundamental aspects of quantum mechanics. Despite the robustness of key exchange, classical post-processing reveals vulnerabilities that an eavesdropper could target. In particula...

Kardashev Scale Quantum Computing for Bitcoin Mining

Bitcoin already faces a quantum threat through Shor attacks on elliptic-curve signatures. This paper isolates the other component that public discussion often conflates with it: mining. Grover's algorithm halves the exponent of brute-force search, promising a quadratic edge to any quantum miner o...

Quantum Secure Biometric Authentication in Decentralised Systems

Biometric authentication has become integral to digital identity systems, particularly in smart cities where it en-ables secure access to services across governance, trans-portation, and public infrastructure. Centralised archi-tectures, though widely used, pose privacy and scalabil-ity challenge...

Communication-Optimal Blind Quantum Protocols

A user, Alice, wants to get server Bob to implement a quantum computation for her. However, she wants to leave him blind to what she's doing. What are the minimal communication resources Alice must use in order to achieve information-theoretic security? In this paper, we consider a single step of...

Quantum Public Key Encryption for NISQ Devices

Quantum public-key encryption PKE, where public-keys and/or ciphertexts can be quantum states, is an important primitive in quantum cryptography. Unlike classical PKE e.g., RSA or ECC, quantum PKE can leverage quantum-secure cryptographic assumptions or the principles of quantum mechanics for...

Efficient Mediated Multiparty Semi-Quantum Secret Sharing Protocol Based on Single-Qubit Reordering

Typical multiparty semi-quantum secret sharing MSQSS protocols require the dealer to possess full quantum capabilities, while the classical users usually need to perform three operations. To address this practical limitation, this paper introduces a new mediated MSQSS protocol that enables Alice,...

Quantum Circuit Benchmarking on IBM Brisbane: Performance Insights from Superconducting Qubit Models

This paper investigates quantum communication using superconducting qubits, emphasizing the simulation and control of quantum systems via IBM Brisbane quantum processor. We focus on implementing fundamental quantum gates and analyzing the evolution of entangled states, which are essential for...

Pulse-Level Simulation of Crosstalk Attacks on Superconducting Quantum Hardware

Hardware crosstalk in multi-tenant superconducting quantum computers poses a severe security threat, allowing adversaries to induce targeted errors across tenant boundaries by injecting carefully engineered pulses. We present a simulation-based study of active crosstalk attacks at the pulse level...

Improving Shor’s Algorithm

We dont have a useful quantum computer yet, but we do have quantum algorithms. Shors algorithm has the potential to factor large numbers faster than otherwise possible, which--if the run times are actually feasible--could break both the RSA and Diffie-Hellman public-key algorithms. Now, computer...

Is quantum teleportation the future of secure communications?

“Beam me up Scotty” will always remain my first association with teleportation. And as it stands now, we are still a long way from teleporting matter, but the teleportation of information has recently made a huge step forward. Researchers in Delft say they have succeeded in teleporting quantum...

Breaking 256-bit Elliptic Curve Encryption with a Quantum Computer

Researchers have calculated the quantum computer size necessary to break 256-bit elliptic curve public-key cryptography: Finally, we calculate the number of physical qubits required to break the 256-bit elliptic curve encryption of keys in the Bitcoin network within the small available time frame...

Factoring 2048-bit Numbers Using 20 Million Qubits

This theoretical paper shows how to factor 2048-bit RSA moduli with a 20-million qubit quantum computer in eight hours. It's interesting work, but I don't want overstate the risk. We know from Shor's Algorithm that both factoring and discrete logs are easy to solve on a large, working quantum...

Want to Use Quantum Computer? IBM launches One for Free

In Brief What would you do if you get access to a Quantum Computer? IBM Scientists launches the world’s first cloud-based quantum computing technology, calling the IBM Quantum Experience, for anyone to use. It is an online simulator that lets anyone run algorithms and experiments on the company's...

It Works! Google's Quantum Computer is '100 Million Times Faster' than a PC

Announcing the results of its experiment, Google says Quantum Computer is More than 100 Million times faster than a regular PC. Two years ago, Google and NASA National Aeronautics and Space Administration bought a D-Wave 2X quantum computer, which they have been experimenting at the U.S. space...