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Abstract: Delegation of authority remains a critical yet insufficiently addressed capability in SelfSovereign Identity (SSI) systems. Building on an existing delegation model that introduced the concept of a Verifiable Mandate (VM) for expressing authority and access rights, this paper extends the approach with a rigorous formalization of delegation semantics, enabling unambiguous reasoning over roles, grants, and constraints. The formal model is aligned with standards from the World Wide Web Consortium (W3C), and its constructs are embedded into an extended credential schema that preserves compatibility with the Verifiable Credentials (VC) data model while introducing delegation-specific attributes. A generalized VM schema is defined, supporting both generic and business-specific instantiations, and ensuring structural and semantic interoperability. Policy compliance is operationalized through a policy-based enforcement architecture, where rules are authored in the Rego language and evaluated at runtime by the Open Policy Agent (OPA). The architecture incorporates trusted registries for schema and policy distribution, allowing verifiers to define and enforce context-specific delegation rules in a modular and interoperable manner. Validation through realistic scenarios, such as postal service and academic use cases, demonstrates how formal semantics, schema validation, and language-based policy enforcement can be combined to enable secure, verifiable, and context-aware delegation in SSI ecosystems.
Keywords: self-sovereign identity, delegation, verifiable mandate, formalization, policy-based enforcement, verifiable credentials, blockchain, language-based security
Published in DKUM: 02.10.2025; Views: 0; Downloads: 9
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Abstract: Pri razvoju decentraliziranih aplikacij (dApps) se tradicionalni razvojni procesi pogosto izkažejo za nezadostne. Tovrstne rešitve zahtevajo večji poudarek na tehničnih, varnostnih in uporabniških vidikih kakovosti aplikacij, kot smo jih sicervajeni pri razvoju klasičnih rešitev. Ker je spreminjanje pametnih pogodb po namestitvi v omrežje verig blokov zahtevno oziroma nemogoče, sta temeljito testiranje ter presoja programske kode ključnega pomena za uspešen razvoj tovrstnih rešitev. Optimizacija stroškov goriva, nujna za izvrševanje programov v javnih omrežjih, predstavlja enega ključnih razvojnih izzivov, ki ga je potrebnoustrezno obravnavati. Poleg tega specifično okolje omrežij veriženja blokov zahteva ustrezne ukrepe za obvladovanje tveganj povezanih z ranljivostmi aplikacij in morebitnimi povezanimi finančnimi izgubami. Nespremenljivost, stroški goriva in zagotavljanje varnosti so le nekateri izmed ključnih razvojnih izzivov, ki jih je treba uspešno nasloviti pri izgradnji kakovostnih in stabilnih decentraliziranih aplikacij. Prispevek obravnava izzive, sodobne pristope in strategije razvoja decentraliziranih aplikacij ter podaja priporočila za njihov zanesljivejši in učinkovitejši razvoj, s čimer naslavlja ključne izzive uvajanja tehnologij veriženja blokov v industrijska okolja ter razvoja pametnih pogodb. Poseben poudarek je namenjen pametnim pogodbam, ki temeljijo na omrežju Ethereum.
Keywords: verige blokov, proces razvoja dApps, testiranje, vzdrževanje, obvladovanje stroškov transakcije, presoje
Published in DKUM: 29.09.2025; Views: 0; Downloads: 11
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Abstract: Self-Sovereign Identity (SSI) is a decentralized, user-centric approach to Identity Management (IdM), that allows users to gain control over their digital identity and data. It brings many advantages and reduces the shortcomings of traditional, centralized IdM systems. Despite its positive features, SSI focuses predominantly on direct interactions between two independent entities. It enables direct identification, authentication, authorization, and access to resources and services where the identity holders are the authenticated bearers of their credentials. On the other hand, it does not address primarily indirect identity control, such as delegation, which is an essential part of life situations and natural human relationships. Delegation is particularly common in organizational contexts, and usually arises from the need for greater efficiency, relief, or distribution of work, collaboration, and cooperation and the inability to perform work, tasks, responsibilities, and duties for various reasons. However, it is relatively unexplored within the SSI framework, and requires additional research efforts and the development of new approaches. Consequently, our research aimed to reduce the aforementioned gap and address delegation in the SSI ecosystem comprehensively. Thus, we present a novel authority and access delegation model utilizing Verifiable Credentials, that enable delegation support for existing use cases, workflows, and processes of organizations and companies, providing resources and services to end users. The model includes delegation building blocks, data objects and data flow, delegation phases and processes, and technology-independent components. It is validated with a case study in the field of Education
Keywords: access delegation, authority delegation, delegation, self-sovereign identity, verifiable credential, verifiable mandate
Published in DKUM: 25.07.2025; Views: 0; Downloads: 2
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Abstract: Artificial intelligence (AI) is one of the key technologies transforming our lives, while the transfer of knowledge and competencies from the academic sphere to the industry and real-world use cases are accelerating yearly. However, during that transition, several significant problems and questions need to be addressed for the field to develop ethically, such as digital privacy, ownership, and control. These are some of the reasons why the currently most popular approaches of artificial intelligence, i.e., centralized artificial intelligence (CEAI), are questionable, with other directions also being explored widely, such as decentralized artificial intelligence (DEAI), which aim to solve some of the most far-reaching problems. This paper aims to review and organize the knowledge in the field of DEAI, focusing solely on studies that fall within this category. A systematic literature review (SLR) was conducted using six scientific databases and additional gray literature to analyze and present the findings of 71 identified studies. The paper’s primary focus is identifying the building blocks of DEAI solutions and networks, tackling the DEAI analysis from a bottom-up approach. Future research directions and open problems are presented and proposed at the end.
Keywords: artificial intelligence, blockchain, cryptography, decentralization, AI, DEAI, decentralized artificial intelligence
Published in DKUM: 23.04.2025; Views: 0; Downloads: 7
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Keywords: zero-knowledge proofs, machine learning, ZKML, decentralized AI
Published in DKUM: 31.01.2025; Views: 0; Downloads: 6
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