Game-theoretic perspective of Ping-Pong Protocol

TL;DR

This paper models the Ping-Pong quantum key distribution protocol as a game to analyze strategies and equilibria, providing insights into security and stakeholder payoffs in two-way QKD protocols.

Contribution

It introduces a game-theoretic framework for analyzing two-way QKD protocols, characterizing strategies, Nash equilibria, and Pareto optimality conditions.

Findings

Identifies strategies leading to Nash equilibria.

Demonstrates conditions for Pareto optimality.

Compares Ping-Pong and LM05 protocols in a game-theoretic context.

Abstract

We analyse Ping-Pong protocol from the point of view of a game. The analysis helps us in understanding the different strategies of a sender and an eavesdropper to gain the maximum payoff in the game. The study presented here characterizes strategies that lead to different Nash equilibriums. We further demonstrate the condition for Pareto optimality depending on the parameters used in the game. Moreover, we also analysed LM05 protocol and compared it with PP protocol from the point of view of a generic two-way QKD game with or without entanglement. Our results provide a deeper understanding of general two-way QKD protocols in terms of the security and payoffs of different stakeholders in the protocol.