xDup: Privacy-Preserving Deduplication for Humanitarian Organizations using Fuzzy PSI

TL;DR

xDup is a privacy-preserving deduplication system for humanitarian organizations, leveraging a new efficient Fuzzy PSI protocol to detect duplicate aid registrations quickly and securely.

Contribution

The paper introduces xDup, a practical deduplication system that is significantly faster than existing solutions and based on a novel efficient Fuzzy PSI protocol.

Findings

xDup is two orders of magnitude faster than current solutions.

The otFPSI protocol improves efficiency for Fuzzy PSI in Hamming Space.

xDup effectively balances privacy and deduplication needs in humanitarian contexts.

Abstract

Humanitarian organizations help to ensure people's livelihoods in crisis situations. Typically, multiple organizations operate in the same region. To ensure that the limited budget of these organizations can help as many people as possible, organizations perform cross-organizational deduplication to detect duplicate registrations and ensure recipients receive aid from at most one organization. Current deduplication approaches risk privacy harm to vulnerable aid recipients by sharing their data with other organizations. We analyzed the needs of humanitarian organizations to identify the requirements for privacy-friendly cross-organizational deduplication fit for real-life humanitarian missions. We present xDup, a new practical deduplication system that meets the requirements of humanitarian organizations and is two orders of magnitude faster than current solutions. xDup builds on Fuzzy PSI, and we present otFPSI, a concretely efficient Fuzzy PSI protocol for Hamming Space without input assumptions. We show that it is more efficient than existing Fuzzy PSI protocols.