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arXiv · 2608.22525

On SSI-based Private Decentralized Bidding

Andreea Elena Drăgnoiu·Nicoleta Dumitru·Ruxandra F. Olimid
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Abstract

Private bidding is a process in which participants submit sealed bids, ensuring that their content remains hidden from other bidders during the bidding window. This is essential in competitive environments to ensure a fair and independent evaluation of all proposals. While (public) blockchain enables decentralized bidding and its transparency offers advantages such as public verifiability, without a Trusted Third Party (TTP), current methods struggle to verify whether a bidder is eligible. We propose a framework that leverages Self-Sovereign Identity (SSI) to address these issues by certifying the bid's eligibility and authenticity using the now-established SSI framework. To allow participants to prove they meet the requirements while keeping their bids secret, our model uses Verifiable Credentials (VCs) and cryptographic primitives such as Zero-Knowledge Proofs (ZKPs).

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Andreea Elena Drăgnoiu, Nicoleta Dumitru, Ruxandra F. Olimid. 2026-08-23. On SSI-based Private Decentralized Bidding. https://arxiv.org/abs/2608.22525

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