Towards Anonymous Crowdsensing: A Smart Contract-Mediated Privacy Framework

Crowdsensing platforms face a fundamental trade-off between data utility and participant privacy, where traditional approaches require users to expose sensitive identity information, creating barriers to widespread adoption. This paper presents a blockchain- based protocol that addresses these privacy concerns through pseudonymous participation and secure data exchange mechanisms. Our approach exploits smart contracts as trusted intermediaries to eliminate di-rect communication between data initiators and contributors, while employing asymmetric cryptography to enable secure key exchange without pre-established channels. The protocol enhances privacy through campaign-specific key pairs that remain unlinkable to participants' persistent identities, contex-tual separation of cryptographic identities, and anonymization sets that obscure individual actions within larger groups. We developed a prototype implementation to verify the correctness of the protocol and to evaluate gas consumption. Through simulation, we assess system performance under varying user dynamics and activity rates. Results confirm the viability of the proposal.