Privacy-Preserving Application of Blockchain Technologies

The blockchain rush and its rapid adoption in our daily life raise new questions and concerns regarding user and data privacy; An important topic that is typically overlooked due to the lack of proper standards and procedures in an under-regulated technology. Identity theft and data breaches are already impacting users on the internet since enterprises are collecting, processing, and storing more consumers’ data in their databases, making them valuable and interesting targets for adversaries and criminal hackers. In most of the existing public blockchains, all transactions are visible in a public ledger where its data can be accessed and processed to profile users for marketing and other purposes without the user’s consent and knowledge. Such enterprises’ interest and influence in blockchain networks and considering their centralized nature and track record can raise the question of data ownership and privacy once again. Blockchain technologies and their decentralized nature are meant to shift the power by giving more control and freedom to users and individuals. But without proper privacy and security controls to protect their data, this could be a false optimism and create a bigger issue instead of solving one. This research aims to contribute, review, and highlight possible solutions for using privacy-focused blockchain technologies and their latest developments to address current and upcoming user and data privacy challenges. Additionally, a Blockchain Reference Model is introduced, which may be used as a reference to standardize the blockchain development.