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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Evaluating OpenSPG Engine for Network Operations</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Beyza Yaman</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Michael Mackey</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Peter Cautley</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Declan O'Sullivan</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>ADAPT Centre, Trinity College Dublin</institution>
          ,
          <addr-line>Dublin</addr-line>
          ,
          <country country="IE">Ireland</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Huawei Ireland Research Centre</institution>
          ,
          <addr-line>Dublin</addr-line>
          ,
          <country country="IE">Ireland</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Telecommunication networks pose challenges for root cause analysis due to complexity, heterogeneous data, and high event volumes. Existing models like RDF and LPG provide only partial solutions when used alone. This paper explores the Semantic-enhanced Programmable Graph (SPG) approach via the OpenSPG engine, which combines property graph flexibility with RDF-inspired semantics. Applied to a telecom use case, OpenSPG shows advantages for event-centric modeling but remains limited in maturity, tooling, and semantic interoperability, highlighting directions for future semantic-enabled network management.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
    </sec>
    <sec id="sec-2">
      <title>2. Related Work</title>
      <p>
        To combine the strengths of RDF and property graphs, several mapping approaches have been developed.
G2GML [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] converts RDF into property graphs for advanced analytics, while ontology-based methods [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]
enable bidirectional transformations to preserve semantics and scalability. Tools such as Gremlinator [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]
and Amazon Neptune’s OneGraph [
        <xref ref-type="bibr" rid="ref10 ref5">5, 10</xref>
        ] further bridge SPARQL and openCypher queries, enhancing
interoperability. A hybrid direction augments property graphs with semantic schemas, integrating
LPG’s simplicity with RDF’s constraints [
        <xref ref-type="bibr" rid="ref3 ref6">3, 6</xref>
        ]. OpenSPG, the first open-source engine based on the
Semantic-enhanced Programmable Graph (SPG) approach, follows this line by enriching property graphs
with semantic capabilities for industrial use [
        <xref ref-type="bibr" rid="ref11 ref6">11, 6</xref>
        ]. In this work, we use OpenSPG to demonstrate a
telecom root cause analysis use case, comparing RDF-based modeling and SPG in terms of semantics
and applicability. Further details and code are available in our report and submitted ISWC Industry
Track paper1. The paper and the report compare RDF-based modeling with the Semantic-enhanced
Programmable Graph (SPG) approach, implemented via OpenSPG, to evaluate their trade-ofs in
semantics, and applicability for telecom network root cause analysis. However, in this paper, the
OpenSPG engine was chosen to explore our use case. The work is practical and demonstrational,
highlighting an industry use case rather than deep formal reasoning.
      </p>
    </sec>
    <sec id="sec-3">
      <title>3. Background</title>
      <p>This section outlines telecom domain challenges and introduces the OpenSPG engine as a hybrid
solution for enterprise use cases.</p>
      <sec id="sec-3-1">
        <title>3.1. Challenges for Network Operations Domain</title>
        <p>There are several operational challenges faced by the network telecom systems2: Modern network
operations face a multitude of data-related challenges that complicate efective monitoring, analysis,
and automation. The overwhelming volume of data from various network planes (management, control,
and data) combined with inconsistent storage formats and fragmented repositories, makes it dificult to
analyse and extract actionable insights. Correlating this data across diferent sources, understanding
service and customer impact, and preserving contextual information such as interface roles or link
functions are particularly dificult. Additional complexities arise from varied data collection methods,
organizational silos, and conflicting sources of truth (e.g., controllers vs. live network state). Altogether,
these issues hinder the development of a unified, machine-readable, and semantically rich view of the
network needed for autonomous decision-making and scalable operations.</p>
        <p>
          Recent work has explored semantic solutions for network operations. Martínez et al. [
          <xref ref-type="bibr" rid="ref12">12</xref>
          ]
proposed the YANG Server Ontology for modeling YANG-based servers and NETCONF interactions, with
RML-based integration guidelines [
          <xref ref-type="bibr" rid="ref13">13</xref>
          ]. They also developed CANDIL [
          <xref ref-type="bibr" rid="ref14">14</xref>
          ], a federated data fabric
unifying heterogeneous network data into a knowledge graph. Similarly, NORIA-O [15] models network
infrastructures and events, though its broad scope challenges consistent multi-domain integration.
        </p>
      </sec>
      <sec id="sec-3-2">
        <title>3.2. OpenSPG Engine</title>
        <p>Released in late 2023, the OpenSPG engine provides an architecture for constructing domain knowledge
graphs using a semantic schema, logical rules, and modular operators based on the SPG approach. It
integrates LLMs for natural language processing and supports layered graph construction, reasoning,
and querying. Data is stored in a graph database (default: Neo4j3), with schema definitions in MySQL;
alignment between table columns and schema properties is essential for proper mapping. Column names
must either be declared as schema properties or mapped to them programmatically. The
OpenSPGSchema defines semantic predicates to enrich LPGs with syntax and semantic constraints. As shown in
Fig. 1, it distinguishes three core types: Entity types (circles in Fig. 1) represent system objects (e.g.,
network elements); Event types (diamonds in Fig. 1) model actions afecting entities over time (e.g.,
route withdrawal); and Concept types (squares in Fig. 1) classify entities and events (e.g., control plane
taxonomy). Distinguishing entity and event types supports semantic graph design by modeling entities
as core objects and events as their interactions or state changes over time.</p>
        <sec id="sec-3-2-1">
          <title>1https://github.com/beyzayaman/openspg 2https://datatracker.ietf.org/doc/html/draft-mackey-nmop-kg-for-netops-02#name-data-overload-from-network3https://neo4j.com/labs/neosemantics/4.3/import/.</title>
        </sec>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4. Application Scenario</title>
      <p>This section presents a network systems use case implemented with OpenSPG, illustrating schema
modeling for causal event relationships. In a network environment, each router first receives advertised
routes, then decides whether to accept them based on rules (like who sent them), and may pass them
on to other peers. These interactions help routers build paths to reach diferent networks, enabling
internet trafic to flow eficiently. A Border Gateway Protocol (BGP) router may lose connection to
one of its upstream peers, triggering a route withdrawal. This means it no longer advertises certain
network prefixes it previously learned from that peer. As a result, neighbouring routers must quickly
ifnd alternative paths or may momentarily lose access to those networks. During this convergence
period, packets destined for the withdrawn prefixes may be dropped, causing a temporary trafic outage
or degradation in service until stable routes are re-established. Thus, it is imperative to identify the
network elements which first causes the problem in the network.</p>
      <sec id="sec-4-1">
        <title>Listing 1: OpenSPG schema for Network Operations</title>
        <p>Listing 1 presents a small script of the OpenSPG schema we created to represent relationships
between diferent events. RouteWithdrawEvent is an event type which belongs to the event concept
class TaxonomyControlPlane and it leads to the event type DroppedTrafficEvent. The subject
of RouteWithdrawEvent is a network element. Designing a hybrid schema involves assigning labels
to properties and defining schema constraints for classes. In the schema, it can be seen that
NetworkElement has an index of on neID and hasNetworkElement property has a multivalue constraint.</p>
      </sec>
      <sec id="sec-4-2">
        <title>Listing 2: Logical concept rule for Network Operations</title>
        <p>‘TaxonomyControlPlane‘/‘RouteWithdraw‘:
rule: [[</p>
        <p>Define (e:RouteWithdrawEvent)-[p:belongTo]-&gt;(o:‘TaxonomyControlPlane‘/‘RouteWithdraw‘) {</p>
        <p>Structure {
}
Constraint {</p>
        <p>R1: e.index == ’route’</p>
        <p>R2: e.trend == ’withdraw’</p>
        <p>There are two ways of creating the relationships, one option is to introduce a new relation type in
the schema which will require a manual upkeep of the schema and bring with it an associated risk
of inconsistencies between the new data and the existing knowledge graph. A second approach is to
create attributes and relationships through logical rules, with the goal of enabling more consistent
and automated modeling. Listing 2 presents the rule for belongTo relationship where only index is
route and trend is withdraw then the instances of RouteWithdrawEvent will belong to the concept of
RouteWithdraw in the TaxonomyControlPlane. As a result of the rule given in Listing 2, we were
able to classify diferent type of instances to their given classes dynamically. A Cypher query along
with its corresponding result is shown in Fig. 2. For property graph management, OpenSPG relies on
Neo4j as its underlying database.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>5. Conclusions</title>
      <p>This paper presents a work in progress investigation on the state-of-the-art methods, as part of their
contribution to the ISWC industry track paper, reflecting both technical competence and a clear
understanding of the underlying concepts in both OpenSPG and RDF approaches.</p>
      <p>Switching from RDF-based modelling to the OpenSPG approach ofers flexibility with schema
definitions but comes with notable trade-ofs in semantics and interoperability. Without RDF’s formal
ontologies and reasoning capabilities, automated inference and standards-based validation (e.g., SHACL)
are limited, increasing reliance on manual interpretation. Interoperability also sufers, as integration
with external linked data sources, reuse of public RDF datasets, and portability between systems become
more complex due to the lack of shared vocabularies and standard query protocols like SPARQL. While
these drawbacks may be less critical in performance-driven, internal domains such as telecom event
analysis, they reduce the universality and cross-system compatibility that are hallmarks of semantic web
solutions. Our use case illustrates how causal relationships between network events can be presented by
employing SPG for modeling complex, event-driven data in network operations. This early exploration
highlights the potential of SPG-based systems in operational domains and lays the groundwork for
future research in semantic modeling for large-scale, event-driven environments.</p>
    </sec>
    <sec id="sec-6">
      <title>Acknowledgement</title>
      <p>This research received funding from Research Ireland [grant number 24/IRDIF/13114] and ADAPT
Researchers are partially funded by the European Regional Development Fund through the ADAPT
Centre for Digital Content Technology [grant number 13/RC/2106].</p>
    </sec>
    <sec id="sec-7">
      <title>Declaration on Generative AI</title>
      <p>During the preparation of this work, the authors used Chat-GPT-4 in order to: Grammar and spelling
check. After using these tool(s)/service(s), the authors reviewed and edited the content as needed and
take full responsibility for the publication’s content.
[15] L. Tailhardat, Y. Chabot, R. Troncy, Noria-o: an ontology for anomaly detection and incident
management in ict systems, in: European Semantic Web Conference, Springer, 2024, pp. 21–39.</p>
    </sec>
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