Protocol Security Analysis for Discrete Modulated Continuous Variable Quantum Key Distribution

量子计算机的出现迫使我们改变保护数据存储和通信结构的加密基础设施。量子密钥分发（QKD）将成为这种新基础设施的一部分，因为它可以提供独立于未来技术和算法进步的实现安全性。为了使QKD与现代光通信技术兼容，允许在更广泛的电信服务提供商市场中采用该技术，必须在概念和实践方面做出许多努力。QKD可用于确保电信基础设施的安全，也可用于向最终客户提供密钥管理服务。成功采用的要求将是稳定的设备，可以无缝地适应现有的基础设施，并使用与现代经典通信设备基本相同的组件。近年来，我们在分析量子密钥分发协议及其光学实现的安全性和性能方面取得了巨大进展。最初的重点是QKD技术，该技术需要能够检测到单个光子，这是可检测到的最小的光量。最近，基于现代差和外差检测技术的QKD系统被开发出来，使用标准的光学检测方案，因为它们被用于现代光通信。这些协议不需要单光子检测，这可能为更便宜、更快的QKD方案开辟了道路。然而，虽然这些协议的一些理想化情况现在可以很容易地分析，但一些理想的协议，即所谓的离散调制连续变量协议，由于缺乏安全证明技术，尚未进行全面的安全性分析。在本提案中，我们将开发适用于这些理想协议的安全证明的新工具和方法。只有有了明确的安全证明，我们才能部署新的方案来保护我们的基础设施。

The emergence of quantum computers forces us to change the cryptographic infrastructure securing our data storage and communication structures. Quantum Key Distribution (QKD) will be part of this new infrastructure as it can provide implementation security independent of future technological and algorithmic advances. Much conceptional and practical effort has to be made to make QKD compatible with modern optical communication technology to allow adoption of this technology within the broader telecom service provider market. QKD could be used to secure the telecommunication infrastructure or also to provide key management service to end customers. The requirement for the successful adoption will be stable equipment that fits seamless to existing infrastructure and use essentially the same components as the modern classical communication equipment.Over the recent years, immense progress has been made in our ability to analyze the security and performance of quantum key distribution protocols and their optical implementation. Initially the focus was on QKD technology that requires technology able to detect single photons, the smallest amount of light detectable. More recently, QKD systems based on modern homodyne and heterodyne detection technology were developed which use standard optical detection schemes as they are used in modern optical communication. No single-photon detection is required for these protocols, opening potentially the path for cheaper and faster QKD schemes. However, while some idealized situations of these protocols can now be readily analyzed, some desirable protocols, so called discrete-modulated continuous variable protocols, have resisted yet a full security analysis due to missing security proof techniques. In this proposal we will be developing new tools and methods for security proofs that are applicable to these desirable protocols. Only with clear formulated security proofs will we be able to deploy the new schemes to secure our infrastructure.