What is a (Digital) Identity Wallet? A Systematic Literature Review

Identity management is crucial for any electronic service that needs to authenticate its users. Different identity-management models have been introduced and rolled out on a large scale during the past decades. Key distinguishing criteria of these models are the storage location of users' identity data and the degree of involvement of central entities such as identity providers, which can potentially track user behavior. Growing privacy awareness has led to a renaissance of user-centric identity-management models during the past few years. In this context, especially the concept of wallets applied to the digital identity domain has recently attracted attention, putting users into direct control of their identity data. Various approaches and solutions relying on this concept have been introduced recently. However, no generally accepted definitions of the concept "digital identity wallet'' and of its related features and implementations exist so far, leading to considerable confusion in this domain. This paper addresses this issue by providing a systematic literature review on wallets applied to the digital identity domain to identify, analyze, and compare existing definitions, features, and capabilities of such solutions. By means of two research questions, this paper thereby contributes to a better understanding of identity wallets and the various recent developments in this domain.