The Internet today lacks an identity protocol for identifying people and organizations. As a result, service providers needed to build and maintain their own databases of user information. This solution is costly to the service providers, inefficient as much of the information is duplicated across different providers, difficult to secure as evidenced by recent large-scale personal data breaches around the world, and cumbersome to the users who need to remember different sets of credentials for different services. Furthermore, personal information could be collected for data mining, profiling and exploitation without users' knowledge or consent. The ideal solution would be self-sovereign identity, a new form of identity management that is owned and controlled entirely by each individual user. This solution would include the individual's consolidated digital identity as well as their set of verified attributes that have been cryptographically signed by various trusted issuers. The individual provides proof of identity and membership by sharing relevant parts of their identity with the service providers. Consent for access may also be revoked hence giving the individual full control over its own data. This survey critically investigates different blockchain based identity management and authentication frameworks. A summary of the state-of-the-art blockchain based identity management and authentication solutions from year 2014 to 2018 is presented. The paper concludes with the open issues, main challenges and directions highlighted for future work in this area. In a nutshell, the discovery of this new mechanism disrupted the existing identity management and authentication solutions and by providing a more promising secure platform.

Current online services rely blindly on authentication providers to perform identity management and authentication. User credentials in these authentication providers are susceptible to large-scale account hacking. Distributed Ledger Teachnology (DLT) in general and blockchain can offer a solution by decentralizing ownership of credentials and a protocol for verifying one's record in an immutable chain of data. Blockchain can create a secure platform for online service providers to authenticate users with no single point of failure and decrease the possibility of attacks and user data leakages via backdoors. The purpose of this research is to analyze the limitations of centralized authentication system and propose a blockchain-based authentication solution to overcome the issues. In this paper we propose a robust, transparent and secure blockchain-based authentication mechanism called AuthChain. The implementation and testing of the proposed web and android native application was successfully completed with a prototype implementation on single node Ethereum Blockchain.