A survey on essential components of a self-sovereign identity

Abstract

This paper provides an overview of the Self-Sovereign Identity (SSI) concept, focusing on four different components that we identified as essential to the architecture. Self-Sovereign Identity is enabled by the new development of blockchain technology. Through the trustless, decentralised database that is provided by a blockchain, classic Identity Management registration processes can be replaced. We start off by giving a simple overview of blockchain based SSI, introducing an architecture overview as well as relevant actors in such a system. We further distinguish two major approaches, namely the Identifier Registry Model and its extension the Claim Registry Model. Subsequently we discuss identifiers in such a system, presenting past research in the area and current approaches in SSI in the context of Zooko's Triangle. As the user of an SSI has to be linked with his digital identifier we also discuss authentication solutions. Most central to the concept of an SSI are the verifiable claims that are presented to relying parties. Resources in the field are only losely connected. We will provide a more coherent view of verifiable claims in regards to blockchain based SSI and clarify differences in the used terminology. Storage solutions for the verifiable claims, both on-and off-chain, are presented with their advantages and disadvantages.

Self-Sovereign Identity in a Globalized World: Credentials-Based Identity Systems as a Driver for Economic Inclusion

“…The public identifying information linked to a DID may include publicly viewable credentials or attestations, or the public key/address of a cryptocurrency wallet. In this way, DIDs may be used in conjunction with blockchain technology and public-private key pairs (Mühle et al, 2018).…”

“…From a technical perspective, self-sovereign identity is generally regarded as a new paradigm of online identity management, whereby individuals and entities can manage their identity-related information (i.e., identifiers, attributes and credentials, or other personal data) by storing them locally on their own devices (or remotely on a distributed network) and selectively grant access to this information to authorized third parties, without the need to refer to any trusted authority or intermediary operator to provide or validate these claims (Mühle et al, 2018). This enables greater control over personal identifying information, or other relevant data about an individual or entity.…”

Distributed Ledger Technology for eHealth Identity Privacy: State of The Art and Future Perspective

“…The issuers create claims about the user which are used as attributes of user identity and store them in the identity repository using the DLT. Meanwhile, any relaying parties want to identify a user or verify a claim or a user proof should access the DLT registry after granting permission from the user itself and make an attestation if the claim is true as is shown in Figure 1a [5]. SSI uses three concepts to identify which are claims, proofs, and attestations.…”

“…DLT identity management is a promising approach to solve the existing digital identity limitation, with the potential of ensuring integrity while sharing information between different healthcare stockholders and grant access to their network without compromising data. Self-sovereign identity (SSI) model is the next identity model that will be implemented on the top of DLT due to its perspective of moving the identity access and management toward users, and make individuals independent from any identity providers [5].…”

The Review of Non-Technical Assumptions in Digital Identity Architectures

“…Another recent trend in IdM is the application of blockchain [25]. Hence, publications have appeared in recent years e.g., conceptualizing essential components of selfsovereign identity [26], user-centric identity built on blockchain [27] and, counter arguments refuting some of widely-held misconceptions on blockchain as a new trust mechanism [28].…”