Hybrid Consensus with Quantum Sybil Resistance
2026-02-25 • Distributed, Parallel, and Cluster Computing
Distributed, Parallel, and Cluster Computing
AI summaryⓘ
The authors explore a way to keep fake users out of decentralized systems by using a special property of quantum states that can’t be copied. They combine this quantum idea with classical methods to create a consensus protocol that's more energy-efficient and faster than traditional ones based on proof-of-work. Their approach also avoids some problems found in proof-of-stake systems. Additionally, they suggest a way to stop spam attacks within their framework.
Sybil resistancedecentralized consensusquantum statesuncloneabilityquantum position verificationproof-of-workproof-of-stakehybrid consensusRandom Oracle modelspam prevention
Authors
Dar Gilboa, Siddhartha Jain, Or Sattath
Abstract
Sybil resistance is a key requirement of decentralized consensus protocols. It is achieved by introducing a scarce resource (such as computational power, monetary stake, disk space, etc.), which prevents participants from costlessly creating multiple fake identities and hijacking the protocol. Quantum states are generically uncloneable, which suggests that they may serve naturally as an unconditionally scarce resource. In particular, uncloneability underlies quantum position based-cryptography, which is unachievable classically. We design a consensus protocol that combines classical hybrid consensus protocols with quantum position verification as the Sybil resistance mechanism, providing security in the standard model, and achieving improved energy efficiency compared to hybrid protocols based on Proof-of-Work. Our protocol inherits the benefits of other hybrid protocols, namely the faster confirmation times compared to pure Proof-of-Work protocols, and resilience against the compounding wealth issue that plagues protocols based on Proof-of-Stake Sybil resistance. We additionally propose a spam prevention mechanism for our protocol in the Random Oracle model.