In recent years, there has been a rapid advancement in technological innovation and related research on collaborative approaches for sharing users' data among enterprises. Research-backed data sharing practices are much needed to strike a balance between user privacy, enhanced user experience, and profit for businesses. The questions of when and what data should be shared to whom, and how the data owner should get credit or incentive to share their data are increasingly a matter of intense debate and research. User data is collected by different parties, for example, companies offering apps, social networking sites, and others, whose primary motive is to have an enhanced business model while giving optimal services to their customers. However, the collection of user data is associated with serious privacy issues. Some data are contributed voluntarily by the user; others are obtained by the system from observation of user activities, or inferred through advanced analysis of volunteered or observed data. The currently dominant model of ownership over user data, usually encoded in the service license agreements, presumes that ownership is transferred from the user to the enterprise collecting it and if shared—to the entire network of businesses.
There are privacy and security problems associated with storing personal data. Even the most prominent online services have experienced security breaches and data theft. When trust resides within a centralized service provider for all the storage of data, it could be affected by centrality issues such as intentionally deleting the user data or not delivering the user data due to a technical failure.
We address all these issues (security, privacy, user transparency and control, and incentives for data sharing) by proposing a new project for user modeling using distributed ledgers and smart contracts, relying on user-controlled privacy and data-sharing policies encoded in smart contracts.