# The eIDAS Regulation: A Survey of Technological Trends for European Electronic Identity Schemes
## 10 eIDAS 2.0 Regulation  
The digital identity landscape has evolved through time, beginning with the most basic model (Centralized identities) and progressing through several stages as additional models are introduced. These methods, as illustrated in Figure 7, are briefly explained in the following:  
**Centralized identities:**: Entities such as administrators manage centralized identities at the system level (e.g., active directory). As a result, the user's identity is determined by these entities and can only be deleted through them. Reliance on a centralized entity frequently leads to a lack of interoperability. The main reason is due to the fact that the user's identity cannot be transferred without further ado, and it must be recreated for another service provider;
**Federated identities:**: aims to break down the hierarchies based on a single authority by providing a central-login solution (IdP) to enable the users to share their identities with different SPs using only one registered credential at the IdP. This solution can solve the problem of password fatigue by providing a Single Sign-On experience and interoperability, but, still, the problem of tracking users across multiple SPs remains unsolved. Indeed, it is possible for the IdP to aggregate information from numerous SPs to generate user profiles, which might cause several privacy issues [68];
**Self-sovereign identities:**: is the next and most recent stage of digital identity management that aims to solve the privacy issues in the previous models by giving the users back control of their own data. The main idea is to shift the control from the centers of the network to the edge of the network to enable direct interaction [69]. Figure 6: Authenticators’ security vs. usability trade-off. At the European level, a concrete effort to provide a European interoperable solution started in 2014 by publishing eIDAS 910/2014 [1] based on a federated identities model. However, as we mentioned earlier, major privacy shortcomings exist within the eIDAS 910/2014 regulation, which is the main reason why the revised eIDAS framework (eIDAS 2.0) promotes the transition from a federated to a self-sovereign identity model. The eIDAS 2.0 amendment proposal [5], published in June 2021, aims to:  
* Provide a highly secure and trustworthy electronic identity solution that enables the user to share only the minimum set of identity data needed by the SP to provide the service requested by the user;
* Introduce a so-called \"European Digital Identity Wallet (EUDIW),\" which may be provided by public authorities or by private entities recognized by MSs and link a citizen's national digital identity to other personal attributes (e.g., driving license or bank account);
* Enhance privacy by decoupling credential issuance from its presentation to SPs; This can blind the IdP from the SP the user interacts with and vice versa. The eIDAS 2.0 proposal defines the EUDIW as \"a product and service that allows users to store identity data, credentials and attributes linked to their identity, to provide them to SPs on request and to use them for authentication, online and offline, and to create qualified electronic signatures and seals.\" Based on the eIDAS 2.0 proposal, the EUDIW plays the role of an eID means to receive, store and share Personal Identification Data (PID), (Qualified) Electronic Attestation of Attributes (Q)EAA, and any other personal data. The European Commission road map for the adoption of the eIDAS 2.0 regulation is presented in Figure 8. To provide a set of common standards, technical specifications, and best practices to serve as a basis for an interoperable, secure, and privacy-preserving implementation of EUDIW, the EU Commission published a first draft of the \"Architecture and Reference Framework (ARF)\" in [70]. The ARF provides a set of functional and non-functional requirements that, by the time of writing this work, are quite abstract, and it does not provide any insights regarding how to satisfy the requirements.