Article

Decentralized Identity: Where Did It Come From and Where Is It Going?

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Abstract

The technology category now widely known as “decentralized identity” and more narrowly as “self-sovereign identity” didn’t even exist four years ago. At that time, the cutting edge of digital identity technology consisted of Internet- scale federated identity protocols such as OpenID Connect and user-centric data sharing protocols such as User-Managed Access (UMA). Then along came Bitcoin and a surge of interest in blockchain and distributed ledger technology (DLT). Although the initial uses of this technology focused primarily on cryptocurrency, it didn’t take long for the digital identity community to begin applying it to digital identity scenarios.

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... As the internet has no built-in identity protocol [1], various approaches have been developed in the past. In the isolated model, online services are at the centre of the identity ecosystem, as each one requires users to register a user account with them, which then can be used together with a password to log in [2]. This leads to many user accounts ("logins"), which are spread among various service providers. ...
... In the federated model, dedicated identity providers are utilised, where the user registers once. Afterwards, their identity can be verified at online services that support the respective identity provider [ 2]. Popular examples include so-called social logins, such as the ones offered by Google, Facebook, and Microsoft. ...
... Self-sovereign identity (SSI) is the most recent approach and enables users to manage their digital identities on their own [2], [6]. In addition to strengthening users, SSI could also provide benefits from an interoperability and process perspective [4]. ...
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Conference Paper
Self-sovereign identity (SSI) is a new paradigm, which puts users back in control of their own digital identity. This does not only strengthen the position of the users but implies new interaction schemes that may improve interoperability and usability. Smart services systems enable the integration of resources and activities and use smart products as boundary objects. As such systems typically involve digital interactions between multiple actors, it can be assumed that utilising SSI has a positive impact on them. To investigate how these potential improvements manifest themselves, we investigate electric vehicle charging as example of a smart service system. At the core of our conceptual analysis is the service process, which we extract from a reference model. Based on a SWOT analysis, we identify areas for transformation and derive an SSI-enabled interaction model for an electric vehicle charging service. The evaluation of the new process shows that SSI can reduce complexity of integration with partners and can provide a better customer experience through simplified registration and authentication. Moreover, SSI might even lead to the disintermediation of actors in the service system. Although SSI is still emerging, our findings underline its relevance as a mechanism to establish trust in smart service systems through the seamless and standardised integration of digital identities for humans, organisations, and things.
... DIDs and the associated cryptographic keys, as well as credentials, are stored by users in so-called digital wallets, for instance on smartphones, computers, or in the cloud with a provider of their choice. Such a system is comparable to the physical credentials, e.g., plastic cards, we carry in our physical wallets [Avellaneda et al., 2019]. Since users fully control their data, this approach has been called self-sovereign [Allen, 2016]. ...
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Preprint
Know your customer (KYC) processes place a great burden on banks, because they are costly, inefficient, and inconvenient for customers. While blockchain technology is often mentioned as a potential solution, it is not clear how to use the technology's advantages without violating data protection regulations and customer privacy. We demonstrate how blockchain-based self-sovereign identity (SSI) can solve the challenges of KYC. We follow a rigorous design science research approach to create a framework that utilizes SSI in the KYC process, deriving nascent design principles that theorize on blockchain's role for SSI.
... Therefore, third parties can verify its integrity without contacting the issuer. SSI provides a similar approach to physical ID cards by using Verifiable Credentials (VCs) (Avellaneda et al. 2019;Mühle et al. 2018). VCs contain identity data about their owner, which are digitally signed by trustworthy authorities using cryptographic techniques . ...
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Article
Due to a steeply growing number of energy assets, the increasingly decentralized and segmented energy sector fuels the potential for new digital use cases. In this paper, we focus our attention on the application field of asset logging, which addresses the collection, documentation, and usage of relevant asset data for direct or later verification. We identified a number of promising use cases that so far have not been implemented; supposedly due to the lack of a suitable technical infrastructure. Besides the high degree of complexity associated with various stakeholders and the diversity of assets involved, the main challenge we found in asset logging use cases is to guarantee the tamper-resistance and integrity of the stored data while meeting scalability, addressing cost requirements, and protecting sensitive data. Against this backdrop, we present a blockchain-based platform and argue that it can meet all identified requirements. Our proposed technical solution hierarchically aggregates data in Merkle trees and leverages Merkle proofs for the efficient and privacy-preserving verification of data integrity, thereby ensuring scalability even for highly frequent data logging. By connecting all stakeholders and assets involved on the platform through bilateral and authenticated communication channels and adding a blockchain as a shared foundation of trust, we implement a wide range of asset logging use cases and provide the basis for leveraging platform effects in future use cases that build on verifiable data. Along with the technical aspects of our solution, we discuss the challenges of its practical implementation in the energy sector and the next steps for testing in a regulatory sandbox approach.
... SSI involves three distinct types of entities [46]: the issuer of an identity document, the holder of the respective document, and the verifier of properties described in the document. An analogy from the physical world serves as an illustration of the basic interactions [13]: An SSI system builds upon digital objects comparable to physical ID cards [47]. Appropriate organizations, such as government authorities, issue the respective ID cards to their holders, who subsequently store them in a physical infrastructure of their choice, such as a wallet. ...
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Preprint
The ongoing digital transformation of the medical sector requires solutions that are convenient and efficient for all stakeholders while protecting patients' sensitive data. One example involving both patients and health professionals that has already attracted design-oriented research are medical prescriptions. However, current implementations of electronic prescriptions typically create centralized data silos, leaving user data vulnerable to cybersecurity incidents and impeding interoperability. Research has also proposed decentralized solutions based on blockchain technology as an alternative, but privacy-related challenges have either been ignored or shifted to complex or yet non-standardized solutions so far. This paper presents a design and implementation of a system for the exchange of electronic prescriptions based on the combination of two blockchains and a digital wallet app. Our solution combines the bilateral, verifiable, and privacy-focused exchange of information between doctors, patients, and pharmacies based on a verifiable credential with a token-based, anonymized double-spending check. Our qualitative and quantitative evaluations suggest that this architecture can improve existing approaches to electronic prescription management by offering patients control over their data by design, a sufficient level of performance and scalability, and interoperability with emerging digital identity management solutions for users, businesses, and institutions.
... Recently, with the emergence of blockchains and DLT systems, the notion of a "self-sovereign" identity [39] has come to the forefront as a means for individuals to obtain control over their digital identities. This desire is not new, and it is as old as the Internet itself. ...
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Preprint
Today there is considerable interest in deploying blockchains and decentralized ledger technology as a means to address the deficiencies of current financial and digital asset infrastructures. The focal point of attention in many projects on digital asset and cryptocurrency is centered around blockchain systems and smart contracts. Many projects seek to make the blockchain as the centerpiece of the new decentralized world of finance. However, several roadblocks and challenges currently face this predominant blockchain-centric view. In this paper we argue that the proper and correct perspective on decentralized economy should be one that is asset-centric, where the goal should be the consistent lifecycle management of assets in the real-world with their digital representation on the blockchain. We introduce the notion of the digital twin to capture the relationship between a real-world asset and its on-chain representation. A digital twin container is utilized to permit off-chain state persistence and on-chain state traceability, where the container can be deployed on the blockchain as well as on traditional application servers. The digital twin container becomes the bridge between legacy infrastructures and the newly emergent blockchain infrastructures, permitting legacy systems to interoperate consistently with blockchain systems. We believe this asset-centric view to be the correct evolutionary direction for the nascent field of blockchains and decentralized ledger technology.
... DIDs and the associated cryptographic keys, as well as credentials, are stored by users in so-called digital wallets, for instance on smartphones, computers, or in the cloud with a provider of their choice. Such a system is comparable to the physical credentials, e.g., plastic cards, we carry in our physical wallets [Avellaneda et al., 2019]. Since users fully control their data, this approach has been called self-sovereign [Allen, 2016]. ...
Article
Know your customer (KYC) processes place a great burden on banks, because they are costly, inefficient, and inconvenient for customers. While blockchain technology is often mentioned as a potential solution, it is not clear how to use the technology’s advantages without violating data protection regulations and customer privacy. We demonstrate how blockchain-based self-sovereign identity (SSI) can solve the challenges of KYC. We follow a rigorous design science research approach to create a framework that utilizes SSI in the KYC process, deriving nascent design principles that theorize on blockchain’s role for SSI.
... By executing performance-based financing of sustainable infrastructure, all actors participating in the infrastructure project would be represented with a decentralized identity (DID) on the blockchain containing a unique ID, a public cryptographic key, and other attribute descriptions of the digital identity (Avellaneda et al., 2019;Davie et al., 2019;Li et al., 2019). A decentralized trust web is established through the verifiable credentials of decentralized identifiers (Lux et al., 2020). ...
Thesis
The United Nations Environment Program Finance Initiative as well as the National Academies of Science, Engineering, and Medicine recognize the need for financial innovations to facilitate transitioning to a sustainable society. To ignore financial solutions is to risk increasing environmental and social cost and the window to limit global warming under 1.5ﹾC. Under-investment in infrastructure has resulted in significant deterioration in functionality and deficiencies in society’s ability to meet present needs without compromising future generation needs from an environmental, social, and economic perspective. The American Society of Civil Engineers estimated that $5.9 trillion USD would be required to bring infrastructure to an adequate state and currently only 56 percent has been committed. This translates to an annual deficit of $259 billion USD from 2020 to 2029. Aside from the built environment, investment deficits are found in incentivizing sustainable practices in agriculture as well. Yet, while government subsidies have attempted to guide these operations towards sustainable outcomes, the capital market instruments have not been executed in farming due to market and definitional frictions. This dissertation sought to achieve three goals: (1) to understand the economic value and environmental cost of unsustainable practices; (2) to explore the potential for technology-based financing models such as blockchain to facilitate sustainability-linked financing mechanisms; and (3) to demonstrate a proof-of-concept to operationalize agricultural outcomes-based financing using blockchain. The regional use case focused on agriculture in the sub-watersheds of the Great Lakes drainage area. The work presented here leverages a number of methodologies to achieve these goals, including novel data fusion approaches, application of econometric theories, as well as blockchain-enabled funding and financing mechanisms. My initial approach applies data fusion and hedonic pricing to quantify the contribution of nitrogen and phosphorus loading on farmland sales transactions. The data sources and fusion process were derived from AcreValue, the United States Department of Agriculture's Gridded Soil Survey Geographic database and the United States Geological Survey's Spatially Referenced Regression on Watershed Attributes database. The results suggest that nutrient loading has significant positive influence on farmland prices such that prices increase with contamination and re-valuations of contaminating farmlands is required. The following chapters leverage technology-based financing using blockchains and decentralized oracle networks to reduce investment barriers for sustainable systems. A framework is presented where trusted data from internet-of-things of infrastructure can inform financial transactions on-chain in an efficient manner. This section employs the Model method to justify and predict how blockchains and oracles can use infrastructure internet-of-things data to streamline performance-based financing mechanisms by creating trust and automation. A performance-based proof-of-concept to incentivize regenerative agriculture practices is then implemented on the Ethereum blockchain. This research element highlights the benefits of implementing performance-based incentives on a blockchain via Transaction Cost Economics (TCE) analysis. The combination of blockchain-based platforms and decentralized oracle networks not only show that payment processes are automated, reducing transaction costs, but also that multiple transaction steps in a typical pay-for outcomes program can be executed using a smart contract. This work reveals the value of leveraging data streams, where insights are generated to understand the boundary conditions for the future design of sustainable infrastructure and practices. The findings of this study serve as a key input for technology-enabled financing models that can lower transaction costs and unlock new capital resources.
... As identifiers and associated identity data are no longer stored in centralized third-party repositories, eliminating a single point of failure, reducing the threat to privacy, enhancing security, and minimizing vulnerabilities connected to personal data misuse, data breaches, and identity-related cybercrimes [11]. Furthermore, SSI is user-centric [6], presenting a shift of power and control from central authorities to decentralized entities, such as users, i.e., identity holders, who must be central to the administration of their own identity and information flow during digital interactions [12] [13] and are responsible for storing their credentials in user agents, i.e., wallets. SSI enables an exchange of claims and credentials without an intermediary, allowing users to attain verifiable credentials from third-party issuers and/or make assertions about themselves, and present them to the relying party, i.e., verifies, requesting proof of identity. ...
Full-text available
Preprint
Self-Sovereign Identity (SSI) is a novel and emerging, decentralized identity approach that enables entities to fully control and manage their digital identifiers and associated identity data while enhances trust, privacy, security, and many other properties analyzed in this paper. The paper provides an overview of the SSI properties, focusing on an in-depth analysis, furthermore presenting a comprehensive collection of SSI properties that are important for the implementation of the SSI system. In addition, it explores the SSI process flow and highlights the steps in which individual properties are important. After the initial purification and classification phase, we then validated properties among experts in the field of decentralized and self-sovereign identity management using an online questionnaire, which resulted in a final set of classified and verified SSI properties. The results can be used for further work on the definition and standardization of the SSI field.
... The identity information itself is not stored in the ledger but in a wallet managed by the user. By controlling what information is shared from the wallet to the requesting third party, users are able to manage their identity and privacy better online [1]. ...
Full-text available
Preprint
We have entered the era of big data, and it is considered to be the "fuel" for the flourishing of artificial intelligence applications. The enactment of the EU General Data Protection Regulation (GDPR) raises concerns about individuals' privacy in big data. Federated learning (FL) emerges as a functional solution that can help build high-performance models shared among multiple parties while still complying with user privacy and data confidentiality requirements. Although FL has been intensively studied and used in real applications, there is still limited research related to its prospects and applications as a FLaaS (Federated Learning as a Service) to interested 3rd parties. In this paper, we present a FLaaS system: DID-eFed, where FL is facilitated by decentralized identities (DID) and a smart contract. DID enables a more flexible and credible decentralized access management in our system, while the smart contract offers a frictionless and less error-prone process. We describe particularly the scenario where our DID-eFed enables the FLaaS among hospitals and research institutions.
... They can keep them on their phones, PCs, or in the cloud with their preferred service provider. A comparable system exists for the actual credentials that we carry in our physical wallets, such as plastic cards [110]. Because people have complete control over their data, it is referred to as self-sovereign. ...
Full-text available
Article
Citation: Shuaib, M.; Hassan, N.H.; Usman, S.; Alam, S.; Bhatia, S.; Agarwal, P.; Idrees, S.M. Land Registry Framework Based on Self-Sovereign Identity (SSI) for Environmental Sustainability.
... Several initiatives have been addressed to provide a decentralized identity model, such as ID2020 [19], Uport [20], Sovrin Foundation [21], or bonifii [22] that allows to develop SSI-based projects [23]. ...
Conference Paper
user-centred identifier enables verifiable and decentralized digital identity, and lead users to control and to generate their own identifiers using systems they trust. This is how Self-Sovereign Identity works. This paper presents the case of universities, where several different agents need their own identifier and shows a digital identity mathematical model. Moreover, the Alastria model for the university context is detailed.
... We suggest that the record of the revocation operation for blockchain applications references the original transaction, indicating that it has been revoked. However, storing assets in transactions that operate in a decentralized and sovereign manner is a recent challenge, which did not even exist four years ago (Avellaneda et al., 2019). Therefore, we propose a model using VC and Decentralized Identifier (DID), which, combined, provide a mechanism to store the revocation operation, and at the same time, keep the sovereignty of the asset's owner. ...
Full-text available
Article
The blockchain's immutability has allowed previously centralized operations to operate in a new way. The possibility of applications having a new architecture is given thanks to the innovative properties of the technology, which brought alternative control designs for distributed systems and allowed applications to work without the need for a central controlling point. The expansion of blockchain to other areas beyond cryptocurrencies has shown the need for applications to implement solutions to deal with corrective operations. Blockchain 3.0 applications bring new solutions for business needs. However, as opposed to immutability, the revoking functionality is much more complex to be implemented in this type of architecture, but paramount to applications resilience, allowing faulty or invalid information to be revoked, ensuring thus that the blockchain can still be trusted. This work assesses and discusses revocation mechanisms to contribute to the technical feasibility of several applications, which require corrective operations. We present a model in the academic area, which can be replicated for other types of systems in other areas.
... Although blockchain technology is not strictly needed for SSI, several SSI projects use a blockchain as a publicly shared and immutable registry for trusted organizations . In the case of SSI, users store their identity-related documents in so-called digital wallet apps on their smartphones (Avellaneda et al., 2019). Different credentials can be stored and presented in combination through these identity wallets, for instance, a digital ID card, a digital vaccination certificate, and a digital ticket . ...
Full-text available
Article
Ticket fraud and ticket scalping activities often cause high costs as well as trust concerns for fans buying event tickets, especially in the secondary ticketing market. To address these issues, several publications and projects have proposed using blockchain technology to enable digital trust and ticket verifiability and thus to improve event ticketing systems. However, these approaches exhibit considerable privacy challenges and fall short concerning reliable, efficient visitor identification, which is necessary for controlling secondary market transactions. We demonstrate how a novel paradigm for end-user digital identity management, called self-sovereign identity (SSI), can be utilized to gain secondary market control. To do so, we follow a rigorous design science research approach to build and evaluate an SSI-based event ticketing framework. Our findings demonstrate that SSI-based event ticketing can enable efficient secondary market control by facilitating a practical implementation of the centralized exchange model. To generalize our results, we derive design principles for the efficient, reliable, and privacy-oriented ticket and identity verification and the use of revocation registries.
... As identifiers and associated identity data are no longer stored in centralized third-party repositories, eliminating a single point of failure, reducing the threat to privacy, enhancing security, and minimizing vulnerabilities connected to personal data misuse, data breaches, and identity-related cybercrimes [11]. Further-more, SSI is user-centric [6], presenting a shift of power and control from central authorities to decentralized entities such as users, i.e., identity holders, who must be central to the administration of their own identity and information flow during digital interactions [12], [13] and are responsible for storing their credentials in user agents, i.e., wallets. SSI enables an exchange of claims and credentials without an intermediary, allowing users to attain verifiable credentials from third-party issuers, and/or make assertions about themselves and present them to the relying party, i.e., verifiers, requesting proof of identity. ...
Full-text available
Article
Self-Sovereign Identity (SSI) is a novel and emerging, decentralized digital identity approach that enables entities to control and manage their digital identifiers and associated identity data fully while enhancing trust, privacy, security, and the many other properties identified and analyzed in this paper. The paper provides an overview and classification of the SSI properties, focusing on an in-depth analysis, furthermore, presenting a comprehensive collection of SSI properties that are important for the implementation of the SSI system. In addition, it explores the general SSI process flow, and highlights the steps in which individual properties are important. After the initial purification and classification phase, we then validated properties among experts in the field of Decentralized and Self-Sovereign Identity Management using an online questionnaire, which resulted in a final set of classified and verified SSI properties. The results can be used for further work on definition and standardization of the SSI field.
... In the EU, Blockchain Partnership Programme (EBP) developed the European Sovereign Identity Institution (ESSIF) based on the European Blockchain Services Infrastructure (EBSI) to provide cross-border public services for all EU citizens all over the EU in 2020. In addition, during the G20 summit, the concepts of self-sovereign identity and decentralized identity have been set as a key discussing topic over many participating countries in 2021 [6]. ...
Full-text available
Article
Blockchain technology has been changing the trust system through machine endorsement and mathematical algorithms, laying a technical foundation for network identity from centralized to decentralized management. The decentralized identity with core features, such as “no need for a management center and self-managed identities” have become a key direction for the evolution of a new generation of digital identity based on blockchain. Internationally, the United States, the EU, and other countries have promoted the technological exploration and application innovation of the decentralized identity, aiming to seize the international discourse power in the digital space. This paper establishes an evaluation model of international engagement in the decentralized identity field and takes the United States as a case to analyze the current development status and international engagement of the decentralized identity from multiple dimensions. Furthermore, it proposes some suggestions for other countries to improve the international engagement in the decentralized identity field.
... The suitability of open-source solutions for standardization has already proven to be a successful tool in several other domains. For example, it proved to be successful in the context of the definition of Decentralized Identity (DID) for blockchain solutions (Avellaneda et al., 2019). ...
Full-text available
Conference Paper
Due to ongoing digitalization, more and more cloud services are finding their way into companies. In this context, data integration from the various software solutions, which are provided both on-premise (local use or licensing for local use of software) and as a service, is of great importance. In this regard, Integration Platform as a Service (IPaaS) models aim to support companies as well as software providers in the context of data integration by providing connectors to enable data flow between different applications and systems and other integration services. Since previous research has mostly focused on technical or legal aspects of IPaaS, this article focuses on deriving integration practices and design-related barriers and drivers regarding the adoption of IPaaS. Therefore, we conducted 10 interviews with experts from different software as a services vendors. Our results show that the main factors regarding the adoption of IPaaS are the standardization of data models, the usability and variety of connectors provided, and the issues regarding data privacy, security, and transparency.
Article
The digital transformation of the medical sector requires solutions that are convenient and efficient for all stakeholders while protecting patients’ sensitive data. One example that has already attracted design-oriented research are medical prescriptions. However, current implementations of electronic prescription management systems typically create centralized data silos, leaving user data vulnerable to cybersecurity incidents and impeding interoperability. Research has also proposed decentralized solutions based on blockchain technology, but privacy-related challenges have often been ignored. We conduct design science research to develop and implement a system for the exchange of electronic prescriptions that builds on two blockchains and a digital wallet app. Our solution combines the bilateral, verifiable, and privacy-focused exchange of information between doctors, patients, and pharmacies through verifiable credentials with a token-based, anonymized double-spending check. Our qualitative and quantitative evaluations as well as a security analysis suggest that this architecture can improve existing approaches to electronic prescription management by offering patients control over their data by design, a high level of security, sufficient performance and scalability, and interoperability with emerging digital identity management solutions for users, businesses, and institutions. We also derive principles on how to design decentralized, privacy-oriented information systems that require both the exchange of sensitive information and double-usage protection.
Full-text available
Article
Self-Sovereign Identity is an emerging, user-centric, decentralized identity approach utilizing some form of decentralized technology. It provides a means for digital identification without reliance on any external authority, enabling entities to control their identity and data flow during digital interactions while enhancing security and privacy. With the rise of blockchain technology, Self-Sovereign Identity is gathering momentum in academia and industry while the number of research papers increases rapidly. Yet Self-Sovereign Identity is still in a young unstructured field in its early stages of research. Thus, a systematic mapping methodology was adopted to provide a coarse-grained overview of decentralized and Self-Sovereign Identity and structure the research area by identifying, analyzing, and classifying the research papers according to predefined parameters, precisely according to their contribution, application domain, IT field, research type, research method, and place of publication. Furthermore, the nature and scope of the research are determined, meanwhile existing research topics, gained insights into trends, demographics, challenges, gaps, and opportunities for future research are also presented.
Article
The Paris Agreement’s decentralized and bottom-up approach to climate action poses an enormous accounting challenge by substantially increasing the number of heterogeneous national, sub-national, and non-state actors. Current legacy climate accounting systems and mechanisms are insufficient to avoid information asymmetry and double-counting due to actor heterogeneity and fragmentation. This paper presents a nested climate accounting architecture that integrates several innovative digital technologies, such as Distributed Ledger Technology, Internet of Things, Machine Learning, and concepts such as nested accounting and decentralized identifiers to improve interoperability across accounting systems. Such an architecture can enhance capacity building and technology transfer to the Global South by creating innovation groups, increasing scalability of accounting solutions that can lead to leapfrogging into innovative systems designs, and improving inclusiveness.
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Federated identity management has allowed the users to dynamically distribute identity information across security domains that increases the portability of their digital identities. Federated identity management is a set of technologies and processes that allow computer systems to dynamically distribute identity information and delegate identity tasks across security domains. Federated identity is a means by which Web applications offer the users with cross-domain single sign-on (SSO) that lets them to authenticate once and then gain access to protected resources and Websites. Federated identity offers solutions to many problems faced by the user in the Web environments, and SSO is the first federated capability that is added by the organizations. Federated identity is less expensive than implementing a high-quality authentication infrastructure because it offloads the authentication task to an IdP.
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The Path to Self-Sovereign Identity
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