The security of Ping-Pong protocol

TL;DR

This paper analyzes the security of the Ping-Pong quantum key distribution protocol against known attacks and proposes a scheme to improve its security, emphasizing the importance of entanglement and operation randomization.

Contribution

It provides a security analysis of the Ping-Pong protocol and introduces a scheme to enhance its robustness against quantum attacks.

Findings

The protocol's security is vulnerable to certain quantum attacks.

A proposed scheme can improve security against specific attack vectors.

Entanglement and operation randomization are crucial for protocol security.

Abstract

Ping-Pong protocol is a type of quantum key distribution which makes use of two entangled photons in the EPR state. Its security is based on the randomization of the operations that Alice performs on the travel photon (qubit), and on the anti-correlation between the two photons in the EPR state. In this paper, we study the security of this protocol against some known quantum attacks, and present a scheme that may enhance its security to some degree.