REWARDS: Privacy-preserving rewarding and incentive schemes for the smart electricity grid and other loyalty systems

In this work we present REWARDS (pRivacy prEserving reWARDing Scheme), a generic framework to be used for reward collection in the smart grid and other loyalty systems. A useful functionality to motivate user participation in such systems is to provide for a privacy-preserving mechanism to reward users for the electricity data they submit to a utility provider. Our lightweight scheme allows participants to earn and redeem incentives in a way that cannot be linked to their actions or identities. While our presentation focuses around the smart electricity grid, the generic character of REWARDS makes it a perfect candidate for other application domains and loyalty systems where user participation is critical to the success of the application. One such important paradigm is mobile crowd-sensing, where users contribute data sensed with their smart devices to a campaign administrator and expect a reward for them. We have analyzed the security properties of our scheme and showed that our reward tokens are indeed privacy-respecting; rewards are unlinkable to each other and token transactions do not leak any information about the user. Additionally, we have showed that our solution is highly efficient in terms of computation, communication and storage overhead, thus guaranteeing good performance in practice.