An Efficient, Anonymous and Unlinkable Incentives Scheme

Incentives systems, such as loyalty schemes or reputation systems, are a popular way to encourage user actions or build a user-service provider relationship. In this paper, the authors describe uCentive, a privacy-preserving incentives scheme that allows users to earn and redeem incentives that cannot be linked to their identities or actions. In addition, users can prove ownership of their incentives without breaking unlinkability guarantees. uCentive also supports forward unlinkability-even if the user's secrets are compromised, they cannot be linked to previous user's actions.