Date Available


Year of Publication


Degree Name

Master of Computer and Information Science (MCIS)

Document Type

Master's Thesis




Computer Science

First Advisor

Dr. Yang Xiao


Decentralized applications (dApps), enabled by the blockchain and smart contract technology, are known for allowing distrustful parties to execute business logic without relying on a central authority. Compared to regular applications, dApps offer a wide range of benefits, including security by design, trustless transactions, and resistance to censorship. However, dApps need to access real-world data to achieve their full potential, relying on the data oracles. Oracles act as bridges between blockchains and the outside world, providing essential data to the smart contracts that power dApps. A significant challenge in integrating oracles into the dApp ecosystem is the Oracle Problem, which arises from the difficulty of securely and reliably providing off-chain data to smart contracts. Trust issues, centralization risks, and data manipulation are some concerns of the Oracle Problem. Addressing these challenges is vital for the continued growth and success of dApps.

In this paper, we propose DEXO, a novel decentralized oracle mechanism designed to tackle the oracle problem by leveraging the power of Trusted Execution Environments (TEEs) and secure attestation mechanisms. DEXO aims to provide a more transparent, decentralized, and trustworthy solution for incorporating external data into dApps, ensuring that the data originates from regular, trustworthy dApp users. By empowering dApp users and developers to contribute diverse data types, DEXO fosters a more dynamic and enriched ecosystem. The proposed DEXO network not only addresses the challenges posed by the Oracle Problem but also encourages greater trust and confidence in the data provided to dApps, ultimately enhancing the overall user experience and promoting further growth in the decentralized application space.

Digital Object Identifier (DOI)