The Exchange Center: A Case Study of Hybrid Decentralized and Centralized Applications in Blockchain

Abstract

Blockchain and smart contract provide a convenient vehicle to build decentralize applications. Among varies Decenrtalized applications (DAPPs), exchange is one of the most mentioned ones. To fully-decentralized an exchange looks somehow like an utopia. Most works tried to use different methods to solve different problems on this subject. According to our observations, the problems caused by blockchain include 1) Long confirmation time, 2) Vulnerable to front running attack, 3) wasting on-chain resource, all these problems make a blockchain based exchange not user friendly. To deal with the above-mentioned problems, a hybrid centralized and decentralized exchange is presented in this work. By simulating the transaction execution processes and eliminating all the unwanted uncertainties, we are confident that the transactions in the proposed exchange center (EC) will be confirmed and executed well on the blockchain, that is, our system allows users to conclude their trades without need of waiting for a long blockchain confirmation time. In conclusion, a Hybrid Centralized and Decentralized Application (HCDAPP) provides a better-quality service, just like a centralized server; at the same time, it also provides a higher-level security, like a decentralized smart contract.