Security of Device-independent Quantum Key Distribution under Sequential Attack
arXiv:2411.16822 · doi:10.1007/s11128-026-05225-x
Abstract
Device-independent quantum key distribution (DI-QKD) leverages nonlocal correlations to establish cryptographic keys between two honest parties while making minimal assumptions about the underlying systems. The security of DI-QKD is grounded in the validity of quantum theory, with Bell violations ensuring the intrinsic unpredictability of observed statistics, independent of the trustworthiness of the devices. While traditional collective QKD attacks assume that the adversary prepares the shared system, we analyse a scenario where the adversary does not control the source and instead interacts sequentially with the travelling system. In this setting, Eve performs an unsharp measurement that produces effective noise while preserving the observed Bell violation. Although such behaviour is already accounted for in existing DI-QKD security proofs, examining it through an explicit sequential interaction offers a concrete and physically motivated example of how these effective statistics can arise in practice. Our analysis further shows that, within a specific parameter regime, this sequential strategy reproduces some features of an optimal collective attack.
12 pages, 5 figures, close to accepted version
References in corpus (60)
- The Security of Practical Quantum Key Distribution
- Bell nonlocality
- Advances in Quantum Cryptography
- Device-independent security of quantum cryptography against collective attacks
- Free-Space distribution of entanglement and single photons over 144 km
- Distillation of secret key and entanglement from quantum states
- From Bell's Theorem to Secure Quantum Key Distribution
- The operational meaning of min- and max-entropy
- Device-independent quantum key distribution secure against collective attacks
- Fully device independent quantum key distribution
- Security in Quantum Cryptography
- All Entangled Quantum States Are Nonlocal
- Multiple Observers Can Share the Nonlocality of Half of an Entangled Pair by Using Optimal Weak Measurements
- Advances in device-independent quantum key distribution
- Unbounded randomness certification using sequences of measurements
- Entropy accumulation
- Efficient quantum key distribution secure against no-signalling eavesdroppers
- Arbitrarily many independent observers can share the nonlocality of a single maximally entangled qubit pair
- Sequential random access codes and self-testing of quantum measurement instruments
- Steering a single system sequentially by multiple observers
- Device-Independent Quantum Key Distribution with Random Key Basis
- Three-observer Bell inequality violation on a two-qubit entangled state
- Sharing of Non-Local Advantage of Quantum Coherence by sequential observers
- Unbounded sequence of observers exhibiting Einstein-Podolsky-Rosen steering
- Facets of bipartite nonlocality sharing by multiple observers via sequential measurements
- Sharing non-locality and non-trivial preparation contextuality using same family of Bell expressions
- Experimental Certification of Sustained Entanglement and Nonlocality after Sequential Measurements
- Detection of genuine tripartite entanglement by multiple sequential observers
- Bell nonlocality, signal locality and unpredictability (or What Bohr could have told Einstein at Solvay had he known about Bell experiments)
- Observation of nonlocality sharing via not-so-weak measurements
- Sharing of tripartite nonlocality by multiple observers measuring sequentially at one side
- Quantum predictions for an unmeasured system cannot be simulated with a finite-memory classical system
- Genuine Einstein-Podolsky-Rosen steering of three-qubit states by multiple sequential observers
- Intercept-resend attacks in the Bennett-Brassard 1984 quantum key distribution protocol with weak coherent pulses
- Experimental Test of Sequential Weak Measurements for Certified Quantum Randomness Extraction
- Device-independent quantum key distribution from generalized CHSH inequalities
- Einstein-Podolsky-Rosen Steering in Two-sided Sequential Measurements with One Entangled Pair
- Noise-robust preparation contextuality shared between any number of observers via unsharp measurements
- Projective measurements are sufficient for recycling nonlocality
- Device-independent quantum key distribution with arbitrarily small nonlocality
- Understanding the interplay of entanglement and nonlocality: motivating and developing a new branch of entanglement theory
- Recycled entanglement detection by arbitrarily many sequential and independent pairs of observers
- Sequential sharing of two-qudit entanglement based on the entropic uncertainty relation
- Single-pair measurement of the Bell parameter
- Quantum Correlation Sharing: A Review On Recent Progress From Nonlocality To Other Non-Classical Correlations
- Sharing nonlocality in quantum network by unbounded sequential observers
- Eavesdropping without quantum memory
- Network nonlocality sharing via weak measurements in the generalized star network configuration
- Device-independent self-testing of unsharp measurements
- Ability of unbounded pairs of observers to achieve quantum advantage in random access codes with a single pair of qubits
- Sharing preparation contextuality in Bell experiment by arbitrary pair of sequential observers
- The future of secure communications: device independence in quantum key distribution
- Unbounded Sharing of Nonlocality Using Projective Measurements
- Resource theoretic efficacy of the single copy of a two-qubit entangled state in a sequential network
- Quantifying the intrinsic randomness in sequential measurements
- Secure and robust randomness with sequential quantum measurements
- Self-testing of multiple unsharpness parameters through sequential violations of non-contextual inequality
- Remote state preparation by multiple observers using a single copy of a two-qubit entangled state
- Secure One-Sided Device-Independent Quantum Key Distribution Under Collective Attacks with Enhanced Robustness
- Robust certification of quantum instruments through a sequential communication game