# Composable security for continuous variable quantum key distribution: Trust levels and practical key rates in wired and wireless networks

@article{Pirandola2021ComposableSF, title={Composable security for continuous variable quantum key distribution: Trust levels and practical key rates in wired and wireless networks}, author={Stefano Pirandola}, journal={Physical Review Research}, year={2021} }

Continuous variable (CV) quantum key distribution (QKD) provides a powerful setting for secure quantum communications, thanks to the use of room-temperature off-the-shelf optical devices and the potential to reach much higher rates than the standard discrete-variable counterpart. In this work, we provide a general framework for studying the composable finite-size security of CV-QKD with Gaussian-modulated coherent-state protocols under various levels of trust for the loss and noise experienced…

## 27 Citations

### Composably secure data processing for Gaussian-modulated continuous-variable quantum key distribution

- Computer SciencePhysical Review Research
- 2022

A Gaussian-modulated coherent-state protocol with homodyne detection in the general setting of composable finite-size security and the high signal-to-noise regime which requires the use of high-rate (non-binary) low-density parity check codes is analyzed.

### Digital synchronization for continuous-variable quantum key distribution

- Computer Science, PhysicsQuantum Science and Technology
- 2022

This work proposes a digital synchronization procedure for a modern CV-QKD system with locally generated local oscillator for coherent reception that is modulation format independent and paves the way for cost-effective QKD solutions that can adapt rapidly to changing environmental conditions.

### Continuous-variable quantum key distribution: security analysis with trusted hardware noise against general attacks

- Computer ScienceNanosystems: Physics, Chemistry, Mathematics
- 2022

Using the full security framework for continuous variable quantum key distribution (CV-QKD), this paper provides a composable security proof for the CV- QKD system in a realistic implementation and showed that the system remains operable at channel losses up to 10.2 dB.

### Security proof for continuous-variable quantum key distribution with trusted hardware noise against general attacks

- Computer Science
- 2022

Using the full security framework for continuous variable quantum key distribution (CV-QKD), this paper provides a composable security proof for the CV- QKD system in a realistic implementation and showed that the system remains operable at channel losses up to 10.2 dB.

### Digital Quantum Key Distribution with Continuous-Mode Formalism

- Materials Science
- 2022

Quantum key distribution (QKD) provides an attractive key-sharing technology for remote users with information-theoretic security. QKD with continuous variables oﬀers extraordinary superiority by the…

### Improved composable key rates for CV-QKD

- Computer Science, Mathematics
- 2023

An improved formula for the composable key rate of a generic CV-QKD protocol under collective attacks is provided and this formula is applied to typical protocols, based on Gaussian modulation, comparing their performance with previous results.

### Sub-Gbps key rate four-state continuous-variable quantum key distribution within metropolitan area

- Computer ScienceCommunications Physics
- 2021

A single-carrier four-state continuous-variable quantum key distribution with sub-Gbps key rate within metropolitan area and secure transmissions up to 25 km is demonstrated and shows the road for future high-rate and large-scale CVQKD deployment in secure broadband metropolitan and access networks.

### Sub-Gbps key rate four-state continuous-variable quantum key distribution within metropolitan area

- Computer ScienceCommunications Physics
- 2022

A single-carrier four-state continuous-variable quantum key distribution with sub-Gbps key rate within metropolitan area and secure transmissions up to 25 km is demonstrated and shows the road for future high-rate and large-scale CVQKD deployment in secure broadband metropolitan and access networks.

### Discrete-modulation continuous-variable quantum key distribution with a high key rate

- Computer Science, PhysicsNew Journal of Physics
- 2023

It is shown that a high key rate comparable to the Gaussian modulation can be achieved using only ten or so coherent states by implementing suitable key map and numerical convex optimization techniques.

### Composable end-to-end security of Gaussian quantum networks with untrusted relays

- Computer Sciencenpj Quantum Information
- 2022

This work theoretically tackle composable security of arbitrary Gaussian quantum networks, with generally untrusted nodes, in the finite-size regime, and puts forward a general methodology for parameter estimation, which is only based on the data shared by the remote end-users.

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