A Sybil-Resistant and Decentralized Market Place

TL;DR

This paper introduces MarketPalace, a decentralized peer-to-peer marketplace that uses self-sovereign identity verification to prevent Sybil attacks and enhance trustworthiness without central control.

Contribution

It proposes a novel decentralized marketplace system utilizing self-sovereign identity to mitigate Sybil attacks, improving upon existing reputation-based solutions.

Findings

Feasibility demonstrated for small regional markets

Effective detection of Sybil identities using self-sovereign identity

Enhanced resistance to fraud in decentralized trading environments

Abstract

Existing centralised market places such as Ebay enable companies to gather large amounts of personal data that can be used to manipulate users. Furthermore, users can frequently perform fraud without severe consequence. Reputation systems only solve this problem partially as malicious users can re-join the network with a new identity if their reputation is too low. By performing a Sybil attack, i.e., joining with multiple seemingly distinct identities, malicious participants can further boost their own reputation. In this paper, we present MarketPalace. MarketPalace relies on a peer-to-peer infrastructure to realize a decentralized market place during trading. Only when registering, users communicate with a central server to verify that they are not Sybils. More concretely, our system leverages self-sovereign identity to detect and undermine repeated joins by the same user. We implemented MarketPalace and demonstrated its feasibility for small regional markets.