Quantum protocols for the millionaire problem with a third party are trivial

Abstract

Recently there were many quantum protocols devoted to solve the millionaire problem and private comparison problem by adding a semi-honest third party. They all require complicated quantum methods, while still leak a non-trivial amount of information to at least one of the parties. But it will be shown here that once the third party is introduced, there are very simple protocols which require quantum key distribution as the only quantum resource, and the amount of information leaked can be made arbitrarily small. Furthermore, even a dishonest third party cannot spoil the protocols. Thus our solutions surpass all existing protocols on both feasibility and security.

The protocol is further improved so that it remains secure even if the third party is distrustful

References in corpus (2)

• The Impossibility Of Secure Two-Party Classical Computation
• Two-Party Quantum Protocols Do Not Compose Securely Against Honest-But-Curious Adversaries

Cited by in corpus (5)

• Entanglement-based wavelength multiplexed quantum communication network
• Quantum private comparison protocol without a third party
• Quantum Private Comparison over noisy channels
• Device-independent quantum private comparison protocol without a third party
• Cryptanalysis and improvement of Wu-Cai-Wu-Zhang's quantum private comparison protocol