A Taxonomic Approach to Understanding Emerging Blockchain Identity Management Systems

Abstract

Identity management systems (IDMSs) are widely used to provision user identities while managing authentication, authorization, and data sharing within organizations and on the web. Traditional identity systems typically suffer from single points of failure, lack of interoperability, and privacy issues, such as enabling mass data collection and user tracking. Blockchain technology has the potential to alleviate these concerns: it can support the ability for users to control the custody of their own identifiers and credentials, enabling novel data ownership and governance models with built-in control and consent mechanisms. Hence, blockchain-based IDMSs, which could benefit both users and businesses, are beginning to proliferate. This work categorizes these systems into a taxonomy based on differences in blockchain architectures, governance models, and other salient features. Context is provided for the taxonomy through the description of related terms, emerging standards, and use cases while highlighting relevant security and privacy considerations. Keywords blockchain; data custody; data ownership; decentralized identifier; distributed ledger; identity management; public key infrastructure; self-sovereign identity; smart contract; user-controlled identity wallet; verifiable credential; zero-knowledge proof Disclaimer Any mention of commercial products or reference to commercial organizations is for information only; it does not imply recommendation or endorsement by the National Institute of Standards and Technology (NIST), nor does it imply that the products mentioned are necessarily the best available for the purpose.

Blockchain Networks:

“…Blockchain-based data stores for status querying can have multiple architectures (see Section 4.4 in [15]). They can be built as smart contract registries that are user-controlled, issuer-or consortium-controlled, or ownerless.…”

“…In particular, they can be used to identify the owners and issuers of stateful tokens (and any other entities whose public key is present in the token). These systems may follow the decentralized identifier (DID) standard [17], and the blockchain-based data stores that they use can have architectures similar to the ones discussed above and further examined in [15]. They may also be complemented by smart contracts for public credentials registries, such as those introduced in ERC-780 [18].…”

“…DID documents usually contain information about the owner (e.g., blockchain address, payout account). DIDs are generated directly by users with some architectures requiring an initial registration (e.g., on some on-chain registry) [15].…”

Blockchain and COVID-19 Pandemic: Applications and Challenges

“…Self-sovereignty for identity management allows the users to own and control their identities without the intervening administrative authorities. It assures that an individual has full control over his data and he can allow or reject the request by the organizations to share personal health data with them [78][79][80][81]. Through self-sovereign systems, the data privacy of an individual with symptomatic symptoms of COVID-19 can be assured as the user can refuse the request of sharing personal health data with a health specialist or researcher.…”

Decentralising the Patent System

“…The patent office has a significant role to play in the regulation of patent-related transactions, and that role may also extend to the policing of suspicious activities on the DLT and putting in place systems that ensure the validity of transactions. Independent of the patent DLT, the use of DLTs for identity management is an active area of research (Shrier et al, 2016;Kuperberg, 2019;Lesavre et al, 2019); these may present much more secure modes of transaction than existing DLTs currently offer.…”