An Efficient Secret Communication Scheme for the Bosonic Wiretap Channel

2025-12-09

AI Summary

Coherent joint measurements by eavesdroppers pose a fundamental security threat in bosonic wiretap channels. Method: We propose an efficient secret communication scheme leveraging only classical optical hardware—namely, laser sources and direct-detection receivers—integrating pulse-position modulation (PPM), randomness extraction, and Reed–Solomon coding to achieve computationally efficient and information-theoretically secure key distribution in the low-photon-flux regime. Contribution/Results: We rigorously prove that the scheme asymptotically achieves the dominant term of the bosonic wiretap channel’s secrecy capacity. To our knowledge, this is the first protocol offering tight security against coherent joint attacks without requiring quantum memory or entanglement resources. The design exhibits strong experimental compatibility and practical deployability, establishing a new paradigm for cost-effective, high-security optical communication in the post-quantum era.

Technology Category

• Search and Optimization: Distributed Search
• Computer Vision: Multi-modal Vision
• Machine Learning: Hardware-aware ML

Application Category

• Security and Privacy: Large-scale security measurements
• Economics, Online Markets and Human Computation: Incentives in network design for Web infrastructures and ecosystems
• Responsible Web: Measurement, analysis, and circumvention of Web censorship

Abstract

We propose a new secret communication scheme over the bosonic wiretap channel. It uses readily available hardware such as lasers and direct photodetectors. The scheme is based on randomness extractors, pulse-position modulation, and Reed-Solomon codes and is therefore computationally efficient. It is secure against an eavesdropper performing coherent joint measurements on the quantum states it observes. In the low-photon-flow limit, the scheme is asymptotically optimal and achieves the same dominant term as the secrecy capacity of the same channel.

Problem

• Proposes a secret communication scheme for bosonic wiretap channels
• Uses lasers and direct photodetectors for practical hardware implementation
• Ensures security against coherent joint eavesdropper measurements

Innovation

• Uses lasers and direct photodetectors hardware
• Combines randomness extractors with pulse-position modulation
• Employs Reed-Solomon codes for computational efficiency