Position Verification with Classical Communication

Position verification is the task of verifying the geographical position of a party using computational tasks and physical bounds on the speed of communication. It has been shown that position verification is impossible in the classical setting, but using non-clonability it is shown that one can construct quantum position verification (QPV) schemes. These schemes are secure against any individual attacker, but can be broken by colluding attackers that share a large amount of entanglement.

In this talk, we will go over a recent quantum position verification protocol developed by Jiahui Liu, Qipeng Liu, and Luowen Qian. We will discuss how they use trapdoor claw-free functions to replace quantum communication channels in QPV protocols with classical channels. We will also discuss entanglement lower-bounds required to break the protocol and give some insight into possible future directions in QPV.

Reference: Liu, Jiahui, Qipeng Liu, and Luowen Qian. "Beating Classical Impossibility of Position Verification." arXiv:2109.07517 (2021).