Improving Query Performance in RaaS: A Framework for Reputation As a Service in Decentralized Marketplaces

Abstract

With the increasing trend toward online shopping, there is an increasing need to provide reliable reputation management systems that aid buyers and sellers in making intelligent and accurate choices. In addition to the centrally controlled systems such as Amazon.com, several decentralized marketplaces are also coming up. Blockchain technologies and the associated smart contracts are found to be suitable to build reputation management systems in decentralized marketplaces. In this paper, we provide a brief overview of RaaS, a framework to manage Reputation as a Service in decentralized marketplaces. RaaS framework has blockchains and smart contracts as its foundation to guarantee transparency and immutability of reviews. In particular, we address the performance issues faced by such blockchain-based reputation systems, and propose two schemes that address the performance challenges. We provide analytical performance predictions and verify, by extensive simulations, the accuracy of our analytical predictions. Our schemes are shown to result in more efficient query execution with enhanced block structure schemes, with an improvement of up to 81\% in query execution responses when compared to earlier work.