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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>Hersonissos, Greece
$ rohit.deshmukh@fit.fraunhofer.de (R. A. Deshmukh); diego.collarana.vargas@fit.fraunhofer.de (D. Collarana)</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>Challenges and Opportunities for Enabling the Next Generation of Cross-Domain Dataspaces</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Rohit A. Deshmukh</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Diego Collarana</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Joshua Gelhaar</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Johannes Theissen-Lipp</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Christoph Lange</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Benedikt T. Arnold</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Edward Curry</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Stefan Decker</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Fraunhofer Institute for Applied Information Technology FIT</institution>
          ,
          <addr-line>Sankt Augustin</addr-line>
          ,
          <country country="DE">Germany</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Fraunhofer Institute for Software and Systems Engineering ISST</institution>
          ,
          <addr-line>Dortmund</addr-line>
          ,
          <country country="DE">Germany</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Insight Centre for Data Analytics, University of Galway</institution>
          ,
          <addr-line>Galway</addr-line>
          ,
          <country country="IE">Ireland</country>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>RWTH Aachen University</institution>
          ,
          <addr-line>Aachen</addr-line>
          ,
          <country country="DE">Germany</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2024</year>
      </pub-date>
      <volume>000</volume>
      <fpage>0</fpage>
      <lpage>0003</lpage>
      <abstract>
        <p>Dataspaces are regarded as a standardized solution for sharing data in a trusted way. However, providing and sharing high-quality data across dataspaces poses several scientific and technical challenges, opening new research avenues. Developing governance models and technologies for supporting cross-domain integration of data and services from the existing single-domain dataspaces represents a significant challenge. In this vision paper, we discuss the challenges for enabling next-generation dataspaces and propose an innovative approach that aims at developing a vision and identifying requirements and building blocks for next-generation dataspaces, followed by defining a roadmap and practical migration paths for the existing dataspaces towards the next-generation dataspaces.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Cross-Domain Dataspaces</kwd>
        <kwd>Interoperability</kwd>
        <kwd>Semantic Interoperability</kwd>
        <kwd>AI</kwd>
        <kwd>Large Language Models</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        Dataspaces are essential for enabling data sharing among participants in a sovereign,
interoperable, and trustworthy manner. They have gained prominence in Europe with the European
Data Governance Act as part of the European Data Strategy1. Dataspaces set the path to a
digital single market where data can flow seamlessly and securely across the borders and
sectors within the EU. In the last few years, due to the increasing need to enable secure and
interoperable data-sharing infrastructures among industries in the EU, dataspaces have been
getting increasing attention from the research community and the industry. However, the siloed
work of several independent initiatives has resulted in various definitions of dataspaces [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ].
To prevent fragmented and heterogeneous implementations of dataspaces, the Data Spaces
Support Centre (DSSC)2 is working towards identifying common guidelines and building blocks
to accelerate the development of dataspaces in Europe. While the DSSC’s harmonization of
dataspace concepts enhances interoperability, establishing compatibility in a cross-domain
dataspace scenario remains an open question.
      </p>
      <p>Dataspaces are currently being established in specific domains 3, such as Manufacturing,
Mobility, Culture, and Healthcare. Interoperability among such domain-specific dataspaces
must be facilitated to enable an efective sharing and reuse of data across domains that will help
companies develop new innovative business models and revenue streams. Research is required
to establish the foundations and technology for this interoperation. This paper identifies gaps
in the existing dataspace eforts, presents the challenges for enabling cross-domain dataspaces
and proposes a novel approach that advocates for a coherent strategy combining semantic
interoperability, human-centricity, trust, data stewardship and service quality.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Current Generation of Dataspaces</title>
      <p>
        Several research initiatives develop architectures and technologies for dataspaces. For instance,
the International Data Spaces (IDS) initiative4 has developed the IDS Reference Architecture
Model and the IDS Information Model [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] to enhance interoperability and sovereignty in data
sharing. While Gaia-X5 also shares these objectives, it additionally covers sovereignty over data
in cloud infrastructures. However, neither IDS nor Gaia-X implements Persistent Identifiers
(PIDs) (Pitfall 1), which have been a key enabler for interoperability in and across research data
infrastructures. Therefore, transferring and evaluating this idea in the context of B2B industrial
data infrastructures, or dataspaces is essential for addressing link rot and identifier clashes [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
      </p>
      <p>
        Most of the initiatives, including IDS and Gaia-X, advocate the use of semantics in
dataspaces [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]; however, its potential is not yet fully utilized in actual implementations (Pitfall 2).
Experts report6 that interoperability is often seen only on the metadata level and not on the
actual data payload level. There are no industry-specific controlled vocabulary and knowledge
graphs in place today. It is, therefore, clear that an efective use of semantics is necessary for
the success of dataspaces. However, the Semantic Web is perceived as complex by developers
and its practical adoption is usually challenging for them [
        <xref ref-type="bibr" rid="ref2 ref5">5, 2</xref>
        ] (Pitfall 3). Therefore, there is
an urgent need for new technological solutions to reduce this complexity and make the use of
semantics in dataspaces user-friendly.
      </p>
      <p>
        The three pitfalls mentioned above are exacerbated by the emergence of cross-domain data
ecosystems, i.e., by the various interaction and exchange relationships among cross-domain
dataspace participants. Data ecosystems enable data reuse, the integration of data users and
data providers, and thus the linking of data to innovative services [
        <xref ref-type="bibr" rid="ref6 ref7">6, 7</xref>
        ]. Enabling a federation
of dataspace ecosystems [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] leads to additional requirements concerning interoperability of
metadata, data, identities, access policies, trust among participants, and pricing and governance
models, etc., that need further research.
      </p>
      <p>2https://dssc.eu/
3https://digital-strategy.ec.europa.eu/en/policies/data-spaces
4https://www.internationaldataspaces.org/
5https://gaia-x.eu/
6https://www.trusts-data.eu/data-spaces-semantic-interoperability/workshop-report-pictures-slides/</p>
    </sec>
    <sec id="sec-3">
      <title>3. Challenges and Opportunities for Next-Generation Dataspaces</title>
      <p>In the evolution of dataspaces, enabling cross-domain interoperation holds the potential to
enable new use cases (Figure 1). This involves several challenges and opportunities:</p>
      <p>
        PID Infrastructure: PIDs play a crucial role in addressing link rot and identifier clashes [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]
and facilitating interoperability. However, existing dataspace infrastructure concepts lack
several requirements. The current PID infrastructure is openly accessible and centralized, which
is problematic for competitive industries. Centralized systems also pose single points of failure.
Examples of existing PID systems include ORCID.org, handle.net, and DOIs.
      </p>
      <p>Data Quality, Incentivization, and Governance Frameworks: In the existing prevailingly
domain-centric dataspaces involving participants at diferent levels of technical maturity,
obtaining high-quality data is a big challenge. It takes a lot of efort, time, and several iterations to get
the data providers to provide high-quality data. Organizational rules govern data provision, and
typically, data providers do not receive any incentives, although their data allow for value-added
services. Therefore, designing an economic model that incentivizes high-quality data provision
and guarantees fair returns for providers is crucial.</p>
      <p>Sector-specificity vs Interoperability: Catering for the needs of sectors and to boost
digitalization and innovation, it is necessary to enable and encourage bottom-up and
sectorspecific initiatives. While doing this, we must avoid silos, and ensure interoperability and
seamless data flow across sectors and borders.</p>
      <p>
        Complexity of Semantic Web and Practicality: Interconnecting dataspaces requires
research on varying levels of granularity and technical depth (ranging from fine-grained service
descriptions with Semantic Web standards to more abstract labelling frameworks [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]), for
ifnding the balance between a practical integration practice and complexity of options. Early
experiments with integrating data standards for domain-specific knowledge models [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] show
that such an integration goes beyond an engineering challenge but poses scientific questions [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]
regarding, e.g., how to delineate universal knowledge representation from application logic,
and the scalability of declarative vs. procedural approaches.
      </p>
      <p>The scientific challenge is to identify a logic for representing data semantics and
communication protocols that is suficiently expressive to capture relevant aspects of domain knowledge
and suficiently flexible to cope with the continuous evolution of data standards while remaining
practically applicable for service providers given their scalability, compatibility, and compliance
constraints. The technical challenge is to make essential services such as the persistent
identification of artefacts scale across dataspaces and to define a process for migrating existing “live”
dataspaces, into which participants have invested development eforts and where businesses are
in operation, and to provide tooling support for executing this process with minimal disruption.</p>
    </sec>
    <sec id="sec-4">
      <title>4. Approach for Enabling Next-Generation Dataspaces</title>
      <p>Our approach to address technical, governance, and economic challenges consists of three
steps: (1) Bottom-up investigation: A thorough exploration, analysis, and evaluation of existing
dataspaces; (2) Top-down ideation: Development of a comprehensive vision for next-generation
dataspaces in a green-field approach, i.e., not bound by limitations of legacy design and
imPrerequisites: Federated PID infrastructure, interoperability
at various levels, trust among participants, availability of
high-quality data, generative AI-based tools
The following requires connections primarily to the
Culture dataspace (DS) X and additionally to some
other DSs as indicated:
Connecting to a DS/federation:
- How do I connect to dataspace X as a company
that wants to share data?
- How can I offer movie showtimes for my theater
available as a CSV dataset through DS X? Can you
make that happen for me? I want to get paid per
API access.
- Create a workflow to fetch and aggregate
showtimes of movies and plays in city C. Display it
on our Portal.</p>
      <p>Using a DS/federation:
- Can you show movie and play showtimes near
me?
- Book 2 tickets for movie M.
- I liked the shooting location in movie M and would
like to visit it. Can you find the location and discover
the best tourism company offers? (Tourism DS)
-anI'ditilnikeeratoryvfiosirt mGerebeacseefdoro5n dmayysp.rCefaenreynocuesp?reAplasroe, User
please avoid polluted places not suitable for
asthmatics. (Tourism, Personal, Health, Green
Deal DSs)</p>
      <p>Information</p>
      <p>Model
Tool with
LLMbased Chat
Interface</p>
      <p>Testing &amp;
debugging
Culture Dataspace X</p>
      <p>Tourism
Dataspace</p>
      <p>Federated
Metadata</p>
      <p>Catalog
Low-Code
Semantic</p>
      <p>Sidecar
Data Provider
Application</p>
      <p>Health
Dataspace</p>
      <p>High-quality
semadnatticaapllayyalonandotated</p>
      <p>Green Deal
Dataspace</p>
      <p>Information</p>
      <p>Model
Federated
Metadata
Catalog
Low-Code
Semantic</p>
      <p>Sidecar
Data Consumer</p>
      <p>Application
Mobility Dataspace
plementation decisions, and (3) Migration roadmap: Development of a strategic roadmap and
practical migration paths from current dataspace systems towards next-generation dataspaces.</p>
      <p>
        Addressing Complexity of Semantics in Dataspaces with User-friendly Tools and
Interfaces: To foster technical interoperability, we propose adapting the widely accepted FAIR
Data Principles (Findable, Accessible, Interoperable, Reusable) [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ] originating from research
data management to dataspaces and Knowledge Graphs [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. Specifically, we aim to develop a
distributed PID infrastructure for persistent identification and identifier mapping, including
service descriptions with Semantic Web standards to more abstract “labeling frameworks”.
Furthermore, to bridge the gap between Semantic Web and dataspaces, our approach includes
using tooling support. We plan to use intuitive, user-friendly tools to enable an efective use of
semantics in dataspaces at every stage in the lifecycle of semantic data–from provision, semantic
enrichment, and matchmaking to composition and consumption.
      </p>
      <p>
        The latest advances in AI make it an excellent technology for improving user interface to
dataspaces. We plan to explore using Large Language Models (LLMs) to automate tedious and
repetitive tasks such as data mapping, translation, and semantic enrichment and integration,
ultimately reducing costs and manual efort. Furthermore, the use of low-code development
environments has been explored before to enable data integration and service composition, e.g.,
in the manufacturing domain [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. We plan to enhance such proven tools with Semantic Web
technologies and LLMs, particularly generative AI, to simplify complex and tedious operations
in dataspaces. We also plan to investigate enhancing LLMs with Knowledge Graphs to reduce
hallucinations, increase deterministic behavior and predictability and thus, data quality.
      </p>
      <p>Addressing Data Quality with Incentivization: Based on the experiences gained from the
existing dataspaces, we aim to establish a robust, flexible governance structure that facilitates
seamless data interoperability, while protecting sovereignty, and ensuring fair data sharing.
Our governance model will also include the aspect of economics for incentivizing the provision
of high-quality data. Firstly, we plan to develop a reward or incentive system that aligns with
the value generated by data. This will encourage more parties to provide high-quality data.
Secondly, we propose a mechanism to evaluate the true value of data by tracking its usage and
assessing its value based on impact and usefulness. This mechanism could be complemented
by trust value-assessment features to strengthen the built-in reward system further, ensuring
fair compensation to data providers proportional to the value and trustworthiness of their data.
Finally, we plan to explore cost recovery models for dataspace sustainability and new business
models enabled by dataspaces, including data sharing, marketplaces, and value-added services,
to create new revenue streams and monetize data innovatively.</p>
      <p>Thus, our novel approach fosters a coherent strategy combining interoperability,
userfriendliness, trust, incentivization, data stewardship and service quality. Future work includes
implementing the presented approach, and developing and evaluating technological and process
building blocks to ensure a smooth migration towards next-generation dataspaces.</p>
    </sec>
    <sec id="sec-5">
      <title>Acknowledgments</title>
      <p>Funded by EU Commission within ’Data Spaces Support Centre’ (grant 101083412), Science
Foundation Ireland (SFI) (grant SFI/12/RC/2289_P2) &amp; German Federal Ministry of Education and
Research (BMBF) within ’WestAI’ (grant 01IS22094C) &amp; ’FAIR Data Spaces’ (grant FAIRDS05).</p>
    </sec>
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