Distributed data provenance: fog computing and blockchains improving privacy control, trust and reliability

Abstract

Data Provenance systems enable tracking of the origin and evolution of information, improving trust among parties. This is an important requirement for a wide range of applications such as food safety, supply chains, and monitoring of epidemic outbreaks. Many of these applications are inherently distributed and require high levels of privacy and trust. Fog computing and Blockchains are recent technological solutions that were born from advancements in Cloud and distributed computing. Fog computing focuses on bringing the Cloud closer to the edge user while Blockchain provides transparency without a trusted centralized entity. Both can be complimentary as Fog computing spreads the data and computer storage while Blockchain can keep it consistent and trustworthy. This dissertation describes an architecture that allows the tracking of data provenance in a widearea distributed Fog layer. While Blockchains are employed to provide transparency, each Fog node has control over what is made public on the Cloud. The architecture proposed in this paper enables fast and reliable data provenance for clients executing in the Fog node using software services that keep the information consistent across all interested parties in the Cloud. Information in the system is associated with a proof of authenticity, but authors have control over the eventual publication of such information.The architecture was built upon the well established provenance model W3C Prov, which simplifies adoption of the framework. An application was developed consisting of a client and a restful API that is able to store and share provenance information in a Blockchain using open standards. Results from extensive tests are reported showing that the proposed architecture performs adequately in several scenarios of varying resources and levels of network reliability.