Privacy-preserving and reward-based mechanisms of proof of engagement

TL;DR

The paper tackles the challenge of producing private, verifiable digital proofs of user engagement (PoE) applicable to a wide range of activities. It proposes a privacy-aware PoE architecture with a decoupled reward mechanism that can be deployed as either a centralized system or a distributed ledger-based solution. Core contributions include detailed protocols for PoE generation, exhibition, and transfer, as well as the integration with incentive schemes such as anonymous vouchers modeled after the WOM platform. A prototype implementation and real-world case studies illustrate the framework's flexibility, privacy guarantees, and potential impact on cultural, educational, and tourism domains.

Abstract

Proof-of-Attendance (PoA) mechanisms are typically employed to demonstrate a specific user's participation in an event, whether virtual or in-person. The goal of this study is to extend such mechanisms to broader contexts where the user wishes to digitally demonstrate her involvement in a specific activity (Proof-of-Engagement, PoE). This work explores different solutions, including DLTs as well as established technologies based on centralized systems. The main aspects we consider include the level of privacy guaranteed to users, the scope of PoA/PoE (both temporal and spatial), the transferability of the proof, and the integration with incentive mechanisms.