Open Geospatial Consortium

Submission Date: 2024-02-08

Approval Date: <yyyy-mm-dd>

Internal reference number of this OGC® document: 24-004

Category: OGC® Standards Working Group Charter

Authors: Jon Harrod Booth, Trond Hovland, Scott Simmons

OGC Geographic Data Files Standards Working Group Charter

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Copyright © 2024 Open Geospatial Consortium

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To: OGC members & interested parties

A new OGC Standards Working Group (SWG) is being formed. The OGC members listed below have proposed the OGC Geographic Data Files (GDF) SWG. The SWG proposal provided in this document meets the requirements of the OGC Technical Committee (TC) Policies and Procedures.

The SWG name, statement of purpose, scope, list of deliverables, audience, and language specified in the proposal will constitute the SWG’s official charter. Technical discussions may occur no sooner than the SWG’s first meeting.

This SWG will operate under the OGC IPR Policy. The eligibility requirements for becoming a participant in the SWG at the first meeting (see details below) are that:

  • You must be an employee of an OGC member organization or an individual member of OGC;

  • The OGC member must have signed the OGC Membership agreement;

  • You must notify the SWG chair of your intent to participate to the first meeting. Members may do so by logging onto the OGC Portal and navigating to the Observer page and clicking on the link for the SWG they wish to join and;

  • You must attend meetings of the SWG. The first meeting of this SWG is at the time and date fixed below. Attendance may be by teleconference.

Of course, participants also may join the SWG at any time. The OGC and the SWG welcomes all interested parties.

Non-OGC members who wish to participate may contact us about joining the OGC. In addition, the public may access some of the resources maintained for each SWG: the SWG public description, the SWG Charter, Change Requests, and public comments, which will be linked from the SWG’s page.

Please feel free to forward this announcement to any other appropriate lists. The OGC is an open standards organization; we encourage your feedback.

1. Purpose of the Standards Working Group

The GDF SWG i chartered to create a major revision to the Geographic Data Files Standard (ISO 20524-1: 2020 and ISO 20524-2: 2020). The GDF Standard has been managed by ISO/TC 204 through five revisions, but this latest revision has been recommended for work first in OGC to take advantage of the OGC diversity of members and modern aspects of the OGC Standards Baseline for encoding options.

2. Business value proposition

The GDF Standard provides a standardized basis for the preparation and exchange of conformant data between various interested parties, which include road operators and administrations, entities working on their behalf, private and public sector survey and mapping companies, and companies providing or supporting the road network navigation services.

3. Scope of work

The GDF SWG will create a multipart Standard to provide at least:

  • a conceptual model;

  • a logical model;

  • a physical model; and

  • one or more encodings.

The SWG will assess the approach to splitting the conceptual, logical, and physical models into separate parts. ISO has prepared and published a Technical Report (ISO TR 19169:2021) which has reviewed the existing GDF Standard (2 Parts) and provides analysis and recommendations that should enable a future revision of the GDF Standard to better align to the principle and concepts used within ISO/TC 211 Standards (coming from the Geographic Information and Geomatics domain). These recommendations address a range of topics including: modularization of the Standard; the structure of the overall model; the concepts and approach to be used in the generalized conceptual model; GDF catalogues; guidance on encoding rules; Aligning terminology between GDF and ISO TC 211 Standards; Aligning GDF time domain syntax with other ISO standards; and Adding epoch value to dynamic coordinate reference system in GDF.

The scope of the conceptual and logical models will be informed by the current GDF data model as well as requirements identified in ISO/TC 204 since the time of publication of ISO 20524-1, 2: 2020. Further refinement of the new model content will be determined in SWG meetings and in consultation with other relevant OGC Working Groups and stakeholder communities.

The existing scope statements for the GDF standard (2 Parts) are as follows.

4. Part 1 scope

This part specifies the conceptual and logical data model and physical encoding formats for geographic databases for Intelligent Transport Systems (ITS) applications and services. The part includes a specification of potential contents of such databases (data dictionaries for Features, Attributes and Relationships), a specification of how these contents shall be represented, and of how relevant information about the database itself may be specified (metadata).

The focus of this part is on ITS applications and services and it emphasizes road and road-related information. ITS applications and services, however, also require information in addition to road and road-related information.

EXAMPLE 1 ITS applications and services need information about addressing systems in order to specify locations and/or destinations. Consequently, information about the administrative and postal subdivisions of an area is essential.

EXAMPLE 2 Map display is an important component of ITS applications and services. For proper map display, the inclusion of contextual information such as land and water cover is essential.

EXAMPLE 3 Point-of-Interest (POI) or service information is a key feature of traveler information. It adds value to end-user ITS applications and services.

Typical ITS applications and services targeted by this document are in-vehicle or portable navigation systems, traffic management centers, or services linked with road management systems, including public transport systems.

The Conceptual Data Model has a broader focus than ITS applications and services. It is application independent, allowing for future harmonization of this document with other geographic database standards.

4.1. Part 2 scope

This part specifies the conceptual and logical data model in addition to the physical encoding formats for geographic databases for ITS applications and services. This document includes a specification of potential contents of such databases (data dictionaries for Features, Attributes and Relationships), a specification of how these contents are to be represented, and how relevant information about the database itself can be specified (metadata). This part further defines map data used in automated driving systems, Cooperative-ITS, and Multi-modal transport.

The focus of this document is firstly on emerging ITS applications and services, such as CooperativeITS and automated driving systems, and it emphasizes road, lane and relevant information on road and lane. However, ITS applications and services also require other information in addition to road and road-related information, which are provided as external databases to connect with GDF and to complement each other. Highly defined public transport databases, for instance, are indispensable in multi-modal transport applications and services in particular. Thus, this document focuses secondly on an expansion of the specification to connect with externally existing databases. It is particularly designed to connect a Transmodel (EN 12896-1 and EN 12896-2) conformant public transport database.

Typical ITS applications and services targeted by this document are in-vehicle or portable navigation systems, traffic management centres, or services linked with road management systems, including public transport systems.

The conceptual data model specified here has a broader focus than ITS applications and services. It is application independent, allowing for future harmonization of this model with other geographic database standards.

4.2. Additional considerations

It is expected that the process of revision of GDF will require some adjustment to the scope statements. Assuming that the Standard is modularized, each Part (module) will require a distinct scope statement. The future Parts addressed physical encoding, in general, may be expected to support a more optional nature, with alternative approaches conforming to the revised GDF conceptual and logical model and catalogues being supported by alternative industry-specified physical encoding approaches.

Further detailed guidance on the basis of modelling road networks from real-world road constructs may be added. Extension of concepts to support modelling of non-road surface transport networks and interconnection with network models for other modes of transport may also be included.

4.3. Statement of relationship of planned work to the current OGC Standards baseline

OGC publishes Standards that describe road and transportation networks, including the following:

Each of these Standards address road data for different or partially overlapping purposes. GDF offers an opportunity to bridge some common elements amongst these Standards and perhaps to provide additional model components to extend road data encoded in other OGC Standards.

As the GDF Standard will include an encoding Part, OGC work in both XML (Geography Markup Language) and JSON (the emerging Features and Geometries JSON Standard) are suitable for consideration for the encoding format.

4.4. What is out of scope?

The SWG will limit the scope of the initial deliverables to the general model expressed in previous versions of the GDF Standard.

4.5. Specific existing work used as starting point

The primary source for the GDF work is the existing GDF ISO Standard, identified above. Also ISO TR 19169.

4.6. Is this a persistent SWG

[x] YES

[ ] NO

4.7. When can the SWG be inactivated

The SWG can be inactivated once a new revision of GDF is published and no requirements are identified for further update.

5. Description of deliverables

5.1. Initial deliverables

The initial deliverables from the SWG will be a conceptual model (and logical model) Standard part. The SWG will then publish one or more encoding parts for the conceptual/logical model.

The SWG anticipates completing a draft of Part 1 suitable for public comment in the first year of operation.

5.2. Additional SWG tasks

Not applicable at the time of initial chartering.

6. IPR Policy for this SWG

[x] RAND-Royalty Free

[ ] RAND for fee

7. Anticipated audience / participants

It is expected that the work to revise GDF would be of broad interest, to organizations preparing road network datasets, service providers supporting (vehicle) navigation services, governmental mapping agencies, and representative road administrations and operators.

8. Domain Working Group endorsement

The Urban Digital Twins DWG, which was chartered to include the former Land and Infrastructure DWG, will be consulted in the chartering process. A Transportation and Mobility DWG is also being considered for charter in the OGC at the time of this SWG chartering activity.

9. Other informative information about the work of this SWG

9.1. Collaboration

The GDF SWG will collaborate using a public GitHub repository to ensure maximum access to non-OGC Member stakeholders who can make valuable contributions to the requirements gathering for this Standard.

9.2. Similar or applicable standards work (OGC and elsewhere)

GDF originated in ISO/TC 204 and thus the expertise from that work is resident in ISO. Collaboration with Working Group 3 of ISO Technical Committee 204 (Intelligent transport systems) and the Joint Working Group between TC 204 and TC 211 (Geographic Information and Geomatics), identified as ISO TC 211 Joint Working Group 11, is foreseen.

Other relevant Standards or specification efforts include the following.

  • Those Standards referenced above that are published by OGC.

  • The Association for Standardization of Automation and Measuring Systems (ASAM) OpenDRIVE standard.

  • OpenTNF.

  • buildingSMART Industry Foundation Classes (IFCs), which, incidentally, share an alignment model with OGC InfraGML.

  • Various national or sub-national Road Data standards, of which there are many.

9.3. Details of first meeting

The first meeting of the SWG will occur via a web meeting platform within two weeks of approval of this charter.

9.4. Projected on-going meeting schedule

The work of the SWG will be carried out primarily by email and web meetings, planned for every two weeks, with face-to-face meetings at each of the OGC Member Meetings.

9.5. Supporters of this Charter

The following people support this proposal and are committed to the Charter and projected meeting schedule. These members are known as SWG Founding or Charter members. The charter members agree to the SoW and IPR terms as defined in this charter. The charter members have voting rights beginning the day the SWG is officially formed. Charter Members are shown on the public SWG page. Extend the table as necessary.



9.6. Conveners

Jon Harrod Booth, representing ISO/TC 204 Trond Hovland, representing ISO/TC 211

10. References

ISO TR 19169:2021 Gap-analysis: To map and describe the differences between the current GDF and ISO/TC 211 conceptual models to suggest ways harmonize and resolve conflicting issues ISO 20524-1:2020 Geographic Data Files (GDF) GDF5.1 - Part 1: Application independent map data shared between multiple sources ISO 20524-2:2020 Geographic Data Files (GDF) GDF5.1 - Part 2: Map data used in automated driving systems, Cooperative ITS, and multi-modal transport