ISO/TR 19174:2025

Geographic information - Securing interoperability among heterogeneous city domain information models

This document analyses a feasible way to accommodate interoperability elements for the data component of a spatial data infrastructure (SDI) and extend the meta model framework for interoperability (MFI) in securing interoperability among heterogeneous domain information models under the smart city context. This document: a) outlines the interoperability issues for city domain information models; b) reviews relevant standards and best practices and examines methodologies or solutions to tackle the interoperability issues; c) supposes a use case and provides an example to secure interoperability among different domain information models using model registry; d) specifies technical requirements in concern about how to apply the interoperability elements of the meta model framework to support the interoperability of smart city services; e) highlights the standardization items to be developed to secure interoperability.

Information géographique — Sécuriser l'interopérabilité entre des modèles d'information hétérogènes dans le domaine de la ville

General Information

• Status: Published
• Publication Date: 22-May-2025
• ICS: 13.020.20 - Environmental economics. Sustainability
• ICS: 35.240.01 - Application of information technology in general
• Technical Committee: ISO/TC 211 - Geographic information/Geomatics
• Drafting Committee: ISO/TC 211 - Geographic information/Geomatics
• Current Stage: 6060 - International Standard published
• Start Date: 23-May-2025
• Completion Date: 23-May-2025

Overview

ISO/TR 19174:2025 - Geographic information - Securing interoperability among heterogeneous city domain information models - is a Technical Report that analyzes how to secure data interoperability in smart-city environments. The document focuses on the data component of a Spatial Data Infrastructure (SDI) and on extending the meta model framework for interoperability (MFI) to enable consistent sharing and reuse of heterogeneous city domain information models. It includes a review of relevant standards and best practices, a registration-and-mapping use case using a model registry, and a set of technical requirements and recommendations for further standardization.

Key technical topics and requirements

• Interoperability analysis: identification of interoperability issues across city domain information models (system, semantic and registry interoperability).
• Meta model Framework for Interoperability (MFI): guidance on applying MFI interoperability elements to support smart city services and cross-domain data exchange.
• Model registry & repository concepts: using a model registry to register, discover and map domain models; integration with metadata registries (MDR) and registries-of-registries (RoR).
• Standards mapping and review: assessment of smart-city, geospatial, IoT and data management standards (e.g., ISO/IEC JTC 1 WG 11, ISO/TC 268, OGC, INSPIRE, OASC MIMs) to identify gaps and alignment opportunities.
• Technical requirements: concrete requirements for registration, mapping, metadata capture (registry summary), and applying MFI elements to enable semantic alignment and service interoperability.
• Use case example: a registration and mapping scenario demonstrating how model registration can secure interoperability among different domain models.

Practical applications and target users

Who will use ISO/TR 19174:2025:

• City planners and smart city program managers seeking consistent data exchange across departments and vendors.
• SDI architects and GIS professionals implementing cross-domain geospatial services and digital twins.
• Standards bodies, registries and platform vendors designing model registries, metadata registries or registry-of-registries.
• System integrators and software developers working on semantic mapping, API design (e.g., OGC APIs, NGSI-LD), and data harmonization for urban services.

Practical uses:

• Establishing model registration workflows to make city information models findable and reusable.
• Defining registry and metadata requirements to support semantic interoperability for urban data (assets, infrastructure, temporal/spatio-temporal attributes).
• Informing procurement and technical specifications for interoperable smart-city platforms and digital twin implementations.

Related standards and references

• ISO/IEC 19763 (MFI and related registry concepts)
• ISO 19115-1 (metadata)
• ISO/IEC JTC 1 WG 11 (smart cities work)
• ISO/TC 268 (sustainable cities and communities)
• OASC MIMs, OGC standards, INSPIRE registry practices

ISO/TR 19174:2025 is a practical guidance resource for organizations implementing interoperable smart city data ecosystems based on registration, MFI principles and cross-domain standards alignment.

Standards Content (Sample)

Technical
Report
ISO/TR 19174
First edition
Geographic information —
2025-05
Securing interoperability among
heterogeneous city domain
information models
Information géographique — Sécuriser l'interopérabilité entre
des modèles d'information hétérogènes dans le domaine de la ville
Reference number
© ISO 2025
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 Terms and definitions .1
3.2 Abbreviated terms .3
4 Interoperability issues for city domain information models . 4
4.1 Overview .4
4.2 Smart city standards and standardization activities .4
4.3 Geospatial standards and standardization activities .6
4.4 Data management and IoT standards and standardization activities .6
4.5 Review of standards and standardization activities.7
5 Registers and registries for SDI interoperability . 9
5.1 System interoperability .9
5.2 Semantic interoperability .10
5.3 Registry interoperability .10
5.4 City domain model registration .11
6 Use case development . .12
6.1 Registration and mapping use case . 12
7 Technical requirements . 16
8 Recommendation.16
9 Conclusion . 17
Bibliography .18

iii
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
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with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
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Any trade name used in this document is information given for the convenience of users and does not
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For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 211, Geographic information/Geomatics, in
collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/TC 287,
Geographic Information, in accordance with the Agreement on technical cooperation between ISO and CEN
(Vienna Agreement).
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
Introduction
Local governments are actively implementing various smart city services. The heterogeneity of private
and public data generated from the smart city services is one of the major concerns standard development
organizations (SDOs) are actively proceeding to solve for interoperability. Information modelling fields are
moving towards integrated geospatial information environments, such as digital twins, cyber-physical
systems and the meta-verse. These trends have produced new needs for standards in both private and
public sectors that enable effective information sharing in terms of the geospatial context for smart city
services. Building efficient and effective interconnectedness and sharing information between silo data
models across domain fields and cities is one of the major concerns to make seamless smart city services
operational.
v
Technical Report ISO/TR 19174:2025(en)
Geographic information — Securing interoperability among
heterogeneous city domain information models
1 Scope
This document analyses a feasible way to accommodate interoperability elements for the data component
of a spatial data infrastructure (SDI) and extend the meta model framework for interoperability (MFI) in
securing interoperability among heterogeneous domain information models under the smart city context.
This document:
a) outlines the interoperability issues for city domain information models;
b) reviews relevant standards and best practices and examines methodologies or solutions to tackle the
interoperability issues;
c) supposes a use case and provides an example to secure interoperability among different domain
information models using model registry;
d) specifies technical requirements in concern about how to apply the interoperability elements of the
meta model framework to support the interoperability of smart city services;
e) highlights the standardization items to be developed to secure interoperability.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1 Terms and definitions
3.1.1
information model
graphical and textual representation of entities and the relationships between them
Note 1 to entry: May also be known as a data model (3.1.5), a conceptual data model, a logical data model, an entity
relationship model, an object class diagram or a database definition.
[SOURCE: ISO/IEC 19763-1:2023, 3.17]
3.1.2
interoperability
capability to communicate, execute programs, or transfer data among various functional units in a manner
that requires the user to have little or no knowledge of the unique characteristics of those units

3.1.3
metadata
information about a resource
[SOURCE: ISO 19115-1:2014, 4.10]
3.1.4
metamodel
model (3.1.5) that explains a set of related models, by defining the language for expressing such models
3.1.5
model
representation of some aspect of a domain of interest using a normative modelling facility and model
constructs
Note 1 to entry: Models can be used to express a set of information requirements, processes, services, roles, goals or
some other aspect of a domain of interest.
[SOURCE: ISO/IEC 19763-1:2023, 3.1]
3.1.6
model registry
information system for registering models (3.1.5)
[SOURCE: ISO/IEC 19763-1:2023, 3.10]
3.1.7
model repository
repository (3.1.8) where models (3.1.5) are stored
[SOURCE: ISO/IEC 19763-1:2023, 3.11]
3.1.8
repository
place where, or receptacle in which, things are or may be stored
Note 1 to entry: In meta model framework for interoperability (MFI) and metadata registry (MDR), a repository is
recognized as a database that stores actual instances that conform to a particular metamodel (3.1.4) or a particular set
of metadata (3.1.3).
[SOURCE: ISO/IEC 19763-1:2023 3.13 — "things are or can be stored" has been revised to "things are or may
be stored," "MDR" has been added and "information system" is revised to "database".]
3.1.9
registry summary
RS
metadata (3.1.3) which refers to an individual registry system or an aggregate of registry systems
[SOURCE: ISO/IEC 19763-6:2015, 4.1.6 — "(RS)" has been added]
3.1.10
registry of registries
RoR
registry that stores registry summary (3.1.9) data showing an individual registry system
[SOURCE: ISO/IEC 19763-6:2015, 4.1.5]

3.2 Abbreviated terms
API application programming interface
BIM building information modeling
CaLAThe cadastre and land administration thesaurus
CRS coordinate reference systems
EPSG european petroleum survey group
ETSI european telecommunications standards institute
FAIR findable, accessible, interoperable, and reusable
GDF geographic data files
GIS geographic information systems
GML geography markup language
ICT information and communication technology
INSPIRE infrastructure for spatial information in europe
IoT internet of things
JSON javascript object notation
LADM land administration domain model
MDR metadata registry
MFI meta-model framework for interoperability
MIMs minimal interoperability mechanisms
NGSI-LD next generation service interface with linked data
OASC open & agile smart cities
OGC open geospatial consortium
RoR registry of registries
RS registry summary
SDI spatial data infrastructure
UML unified modeling language
WFS web feature service
W3C world wide web consortium
XML extensible markup language
UN united nations
OMG object management group
4 Interoperability issues for city domain information models
4.1 Overview
Governments and institutions promote open data initiatives, enabling citizens to access and utilize their
data via the internet, potentially driving innovation in both public and private sectors. A challenge citizens
face is to access, share and interconnect diverse public datasets, which can be analyzed to enhance value
through the addition of valuable information and knowledge. The heterogeneity of city domain information
models is a critical issue to be addressed for its successful implementation. SDOs actively work to resolve
heterogeneity issues for better interoperability, presenting reference models and guidelines for data
exchange and sharing. The complexities of exchanging and sharing city domain information models requires
a multifaceted approach to standardization, not confined to a single standard domain. This document
explores standards and standardization activities from three domains relevant to the exchange and sharing
of city information.
4.2 Smart city standards and standardization activities
— ISO/IEC JTC 1/WG 11 - Smart cities: JTC 1/WG 11 leads JTC 1's smart cities standardization program,
addressing the need for smart city ICT standards and advancing projects on smart city ICT reference
architecture, semantic interoperability and open city data. The ICT standards developed by JTC 1/WG
11 focus on six topics, including "SmC (Smart City) Knowledge Management" which is closely related to
exchanging and sharing city domain information models (see Figure 1). The ISO/IEC 5087 series aims to
achieve semantic interoperability with three levels: foundation (ISO/IEC 5087-1), city (ISO/IEC 5087-2),
1)
and service (ISO/IEC 5087:— ). This approach ensures integrated and interoperable city data, leveraging
existing models and enhancing urban knowledge management. To ensure trustworthy exchange and
sharing of city domain information models, smart cities need standards for evaluating the reliability of
knowledge used in applications like urban planning and citizen services. The ISO/IEC 30145-2 framework
proposes creating a trustworthiness evaluation framework, methods for data traceability, metrics
for trustworthiness attributes, and practical guidelines for domain-specific knowledge (see Figure 2).
1) Under development. Stage at the time of publication: ISO/IEC WD 5087-4:2025.

Key
1 relevant area of city domain information model
Figure 1 — Relevant standardization area of the city domain information model in JTC1/WG 11
[4]
works, mapping into smart city standards landscape and layers
Figure 2 — The framework of smart city knowledge management (ISO/IEC 30145-2:2020)
— ISO/TC 268, Sustainable cities and communities: ISO/TC 268 presents guidelines on data exchange and
sharing for smart community infrastructure (ISO 37156), which include nine principles for data exchange
and sharing. Four of these principles are closely related to geospatial information interoperability:

a) Community infrastructure data should be available for exchange and sharing,
f) Data should use spatial methods for positioning and controlling urban infrastructure objects,
g) Data should include temporal information to manage changes in community infrastructure, and
h) A systematic approach with identifiable data attributes should be used to facilitate
interoperability. tests.
— Open & Agile Smart Cities (OASC): The 10 Minimal Interoperability Mechanisms (MIMs) by OASC ensure
[7]
essential interoperability for data, systems and services in smart cities. Among these, MIM7 - Places,
focuses on geospatial information and collaborates with MIM2 for data harmonization. It supports MIM1
in managing and exchanging context information related to data models. MIM7 aims to streamline data
sharing and integration across cities and stakeholders, enhancing the utility of geospatial data for urban
management. MIM7 emphasizes the interoperability of spatial and spatio-temporal data. It mandates
using OGC standards (like WFS and OGC API features) for service interfaces and ensuring unique
[8]
identifiers according to the INSPIRE directive or relevant W3C guidelines. Recommendations include
using standard encodings (GeoJSON, GML, GeoPackage and CityGML) and considering a proxy OGC API.
4.3 Geospatial standards and standardization activities
[8]
— The INSPIRE register federation: The European Commission operates a central registry, INSPIRE, to
manage code lists and themes. Local registers maintain extended values and other use cases. Registers
help eliminate ambiguities in data exchange and aid in user interface internationalization. A central
access point, the Register of Registers (RoR), was established to navigate the INSPIRE federation and is
publicly accessible.
[9]
— The European Geological Services code list registries: The European Geological Services enhanced
their code list registries by integrating new vocabularies and subsequently joining the INSPIRE Register
Federation, a centralized resource for vocabulary access. This registry can now be extended for use in
other geoscientific projects. Geological data, including comprehensive borehole and sample information,
are now available through a linked data approach, with semantic consistency maintained via the Borehole
Conceptual Model, which is grounded in various pre-existing models and specifications.
[10]
— International Code List Management for Land Administration: The ISO LADM and OGC LandInfra
standards use different code lists for similar domains, indicating a need for semantic tools to align them.
The Cadastre and Land Administration Thesaurus (CaLAThe), if updated and integrated with these lists,
could provide a consistent framework. The OGC's strategy of registering its code lists in a triple store
could centralize access through a single portal. An expert consultation body is suggested for maintaining
the portal and identifying revisions, potentially leading to updates in the code lists.
[11]
— ISO Geodetic Registry: The ISO Geodetic Registry, developed by the ISO/TC 211, Geographic
information/Geomatics, provides parameters for global and regional CRSs and their transformations,
conforming to relevant ISO International Standards, such as ISO 19111. The European Petroleum Survey
Group (EPSG) maintains a Geodetic Parameter Registry for defining coordinate reference systems (CRSs)
and their transformations. The Geodetic Registry is a comprehensive database that stores and provides
access to essential geodetic parameters used in various applications. It serves as a centralized repository
for information related to coordinate systems, datums, ellipsoids, projections and other geodetic
reference systems. The registry ensures consistency and standardization in geodetic measurements,
promoting accurate spatial data interoperability across different systems and disciplines.
4.4 Data management and IoT standards and standardization activities
— ISO/IEC JTC 1/SC 32, Data management and interchange: ISO/IEC 19763-1 is about the meta-model
framework for interoperability (MFI) and aims to enable interoperability between various industry-
specific registries. Due to their domain-specific standards, these registries often face compatibility
issues. MFI uses a meta-model to create a registry summary (RS), recording the registry's nature,
content and access information. Each registry can publicly share its RS, allowing users from different
domains to build a dedicated RoR based on their interests.

— ETSI Context Information Management Industry Specification Group: The ETSI Context Information
[13]
Management Industry Specification (NGSI-LD) supports the exchange and sharing of city domain
information models, including geospatial data. Context information management integrates data from
IoT devices and various sources, offering comprehensive access, sharing and analysis through a uniform
interface. The standard provides structured status information about real-world entities, enabling
event detection and context-based data discovery. Applications can query and subscribe to current and
historical data, including geospatial information, ensuring updated status awareness. Harmonized data
models facilitate interoperability, allowing systems to communicate effectively across different cities and
sectors, supporting smart cities, utilities, and industry. It features a meta-model that ensures semantic
interoperability by defining entities, properties and relationships, with support for geospatial and
temporal properties. NGSI-LD also offers architectural considerations, including centralized, distributed
and federated architectures, enabling flexible and efficient data management. These standards facilitate
consistent, scalable and interoperable solutions for managing diverse urban data across different
domains and applications.
4.5 Review of standards and standardization activities
ISO/IEC JTC 1/WG 11 on smart cities, ISO TC 268 on sustainable cities and communities, and Open & Agile
Smart Cities (OASC) are leading the development of international standards and standardization activities for
smart cities. ISO/IEC JTC 1/WG 11 focuses on smart city ICT standards, including semantic interoperability
through the ISO/IEC 5087 series. ISO/TC 268 emphasizes data exchange for smart community infrastructure
with principles for geospatial interoperability (ISO 37156). OASC promotes interoperability for smart city
data using its 10 Minimal Interoperability Mechanisms, particularly MIM7, which focuses on geospatial data
integration and harmonization.
The INSPIRE register federation, operated by the European Commission, manages code lists and themes
through a central registry and local registers. The European Geological Services enhanced their code lists
and joined the INSPIRE federation, supporting geoscientific projects with semantic consistency. The ISO
LADM and OGC LandInfra standards highlight the need for semantic alignment of code lists, suggesting a
centralized portal managed by an expert body. The ISO Geodetic Registry provides global and regional CRS
parameters, ensuring standardized geodetic measurements and promoting spatial data interoperability.
ISO/IEC JTC 1/SC 32's MFI enhances interoperability between industry-specific registries by creating and
sharing RSs to build an RoR. The ETSI Context Information Management (NGSI-LD) specification supports
the exchange and sharing of city domain information models by integrating IoT and other data sources
through a uniform interface. NGSI-LD ensures semantic interoperability with structured data on real-world
entities, enabling event detection, data querying, and subscription across centralized, distributed and
federated architectures. This facilitates comprehensive and efficient urban data management.
Heterogeneity issues in data exchange and sharing among city domain services are common concerns
addressed by technology-focused standardization groups like ISO/TC 211, ISO/TC 268/ SC1, ISO/IEC JTC
1/SC 32, and ETSI, as well as smart city-focused groups like OASC and ISO/IEC JTC 1/WG 11. These domain
standards specify requirements of utilizing spatial information for effective information exchange and
s
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