A Survey on Blockchain-based Identity Management and Decentralized Privacy for Personal Data

In the digital revolution, even secure communication between individuals, services and devices through centralized digital entities presents considerable risks. Having service providers continue to offer their centric solutions is inefficient in terms of duplication, has serious security lacunae and is cumbersome to the users. The self-sovereign Identity concept, which includes the individual's consolidated digital identity and verified attributes, enables the users of data to exert their ownership and gain insights from their data's usage. The authentication and verification of digital identity is essential to achieve the privacy and security of distributed digital identities. In this paper, we provide a coherent view of the central concepts of self-sovereign Identity, including the components of identity proofing and authentication solutions for different self-sovereign Identity solutions. We discussed an overview of Identity management approaches, introducing an architecture overview as well as the relevant actors in such a system and blockchain technology as solution for distributed user-centric identity. Finally, we discuss the existing solutions and point out the research gaps and elaborate challenges and trade-offs towards building a complete identity management system.