Privacy Preserving Reputation Based Medical Services Scheme Using a Variant of ElGamal

Reputation Based schemes are gaining popularity in all spheres of the service industry. In this paper, we have proposed a privacy preserving secure reputation based medical services system. This system enables Medical Users to get a reputation score of a Medical Service Provider before engaging in any services. This kind of approach ensures that the Medical User has some apriori information of the quality of service to expect from a Medical Service Provider. Our proposed scheme uses a variant of the ElGamal cryptosystem. It is privacy preserving in the sense that both the Medical User making the query and the Medical Service Provider remain anonymous throughout the process. Compared to other reputation based schemes our scheme offers more security services than most existing schemes.