Active beam splitting attack applied to differential phase shift quantum key distribution protocol

TL;DR

This paper introduces a new active beam splitting attack on the differential phase shift quantum key distribution protocol, highlighting vulnerabilities in its practical implementation and potential security risks.

Contribution

The paper proposes a novel active attack method exploiting partial information extraction to compromise the protocol's security.

Findings

The attack can successfully extract information without detection.

The attack demonstrates vulnerabilities in the protocol's resistance to active attacks.

Implications for improving security measures in quantum key distribution systems.

Abstract

The differential phase shift quantum key distribution protocol is of high interest due to its relatively simple practical implementation. This protocol uses trains of coherent pulses and allows the legitimate users to resist individual attacks. In this paper, a new attack on this protocol is proposed which is based on the idea of information extraction from the part of each coherent state and then making decision about blocking the rest part depending on the amount of extracted information.