The ONTOCHAIN project has progressed through its 3 phases, each marked by a distinct open call:
Call 1 - Research:
The primary aim of this call was to establish the ONTOCHAIN framework as a human-centric, decentralized, and trustworthy solution based on existing technologies. It has lead to the revision of the initial architecture and component diagram design by the core consortium before Call 1(Figure 1).
FIGURE 1
ONTOCHAIN architecture is structured with key modules that collectively enhance functionality and security:
A Distributed Ledger module establishes a decentralized execution environment, ensuring heightened security and transparency across the entire ecosystem,
An Ontologies module introduces trusted services, emphasizing data integrity in the management of web ontologies.
An Application Protocols layer provides essential functionalities such as Data Provenance, Reputation Models, and Decentralized Oracles. They serve as the foundation for higher-level application solutions, which are built upon the core Blockchain-based services found at the Core Protocols layer. This layer includes Smart Contracts, Identity Management, Secure Decentralized Storage, Certification, Authorization, and Data Semantics.
The Interoperability module and protocols play a multifaceted role. They act as the backbone, interconnecting various modules and providing the ONTOCHAIN Gateway API—a primary entry point for application developers but also supply essential services and building blocks to all components, covering decentralized storage, identity management, and data certification.
Call 2 - Protocol Suite and Software Ecosystem Foundations:
The objective of this call was to elaborate upon ONTOCHAIN architecture and components obtained after OC1 as well as to upgrade the ONTOCHAIN ecosystem to host ONTOCHAIN’s trustworthy data, metadata and services, and specific software solutions that can be used widely, further extending the use cases and the architectural features delivered by Call 1.The successful completion involved projects related to decentralized oracles, market mechanisms, interoperability, network design, semantic marketplaces, and data provenance. The ONTOCHAIN architecture was also upgraded to accommodate additional services and functionalities as depicted in Figure 2.
FIGURE 2
Call 3 - Application and Experimentation:
The objective of Open Call 3 was to develop interoperable and sustainable applications that build on top of ONTOCHAIN software services delivered in OC1 and OC2 and that employ both Semantic Web and Blockchain concepts to enhance data quality aspects as well as the trustworthiness of data communication and handling processes. Applications should cover real needs of end users from various vertical domains/vital sectors of the European economy. Call 3 has led to the upgrading of the ONTOCHAIN architecture and component diagram adding other services and functionalities for Application developers. It has demonstrated the value of ONTOCHAIN frame in developing useful applications covering different aspects and verticals such as DAO, digital content and data analytics, marketplaces, automotive, distribution logistics, public services, credibility management, healthcare, real estate as presented in the ONTOCHAIN ecosystem and frame represented in the next figure.
FIGURE 3