Secure Rewarding Schemes

In this paper, we propose a secure rewarding scheme. I n the scheme, a reward provider publishes a problem, and provides a reward f o r a person who can supply h im a satisfactory solution of the problem. The first qualified claimant with satisfactory solution of the problem is selected to obtain the reward. The selected claimant can obtain the reward from the reward provider without revealing his identity. Nobody except the selected claimant can get the reward, and the provider cannot decline the selected claimant his entitled reward. I n addition, we also propose another secure rewarding scheme with two-way untraceability t o protect the privacy o f the reward provider as well.