Draft Spatial Data on the Web Working Group Charter

This draft charter has been superseded by the January 2015 version. Please do not refer to this document.

What are the best examples of data-driven Web applications you've ever seen? The updates to Open Street Map after the Haiti earthquake? The mapping of all 9,966,539 buildings in the Netherlands? The NHS Prescription data? Things like SF Park that help you 'park your car smarter' in San Francisco using real time data? The maps, satellite and street level images offered by search engines?

All these and many, many more data-driven applications have geospatial information (GI) at their core; it is a major element in defining context for knowledge that can then be exposed in many different ways to end users. The societal, economic and scientific benefits of integrating GI into commercial and institutional processes is potentially huge. Very often the common factor across multiple datasets is the location data, and maps are crucial in visualizing correlations between data sets that may otherwise be hidden.

Having a clear strategy as to how GI is best integrated with data on the Web is paramount. Commercial operators, including search engines, invest a great deal of time and effort in generating geographical databases which are mirrors to Web content with the geographical context often added manually or at best semi-automatically. This process would be substantially aided if data were published on the Web with the appropriate geographic information at the source, thus allowing discovery and access using the standard mechanisms of the Web.

'Geo' is not the only spatial data. In healthcare, for example, polygons may represent pathology tissue segmentation extractions that can be subjected to spatial analysis. Whilst prioritizing geospatial use cases, in so far as is practical, the WG will take account of the needs of other users of spatial technologies.

The term coverage is used to describe a feature whose properties vary with space and / or time; for example, the variation of air temperature within a given geographic region, or the variation of flow rate with time at a hydrological monitoring station.

The Linking Geospatial Data workshop recognized that many relevant standards already exist. These include informal 'community standards' that enjoy widespread adoption (GeoJSON being the prime example) and others for which the formal standardization process has not been completed. Where standards have been completed there are competing ideas and engineers are often unsure which ones to adopt. With these factors in mind, the mission of the Spatial Data on the Web working group is to clarify and formalize the relevant standards landscape. In particular:

  1. to determine how spatial information can best be integrated with other data on the Web;
  2. to determine how machines and people can discover that different facts in different datasets relate to the same place, especially when 'place' is expressed in different ways and at different levels of granularity;
  3. to identify and assess existing methods and tools and then create a set of best practices for their use;
  4. where desirable, to complete the standardization of informal technologies already in widespread use.

The Spatial Data on the Web WG is part of the Data Activity and is explicitly chartered to work in collaboration with the Open Geospatial Consortium (OGC) as described in Dependencies & Liaisons.

@@@Join the Spatial Data on the Web Working Group@@@. (Link to be added if charter approved)

End date 31 December 2016
Confidentiality Proceedings are public
Initial Chairs Kerry Taylor, CSIRO
Ed Parsons, Google
Initial Team Contacts
(FTE %: 20)
Phil Archer
Usual Meeting Schedule Teleconferences: weekly
Face-to-face: twice annually, ideally alternating between an OGC TC and W3C's TPAC


The scope of the Spatial Data on the Web Working Group, SDWWG, is Web technologies as they may be applied to location. Where relevant, it will promote Linked Data using the 5 Stars of Linked Data paradigm, but this will not be to the exclusion of other technologies.

Out of Scope

The Spatial Data on the Web Working Group must be mindful of the needs of front end Web developers, however, it will not develop any geospatial or map rendering technologies. In other words, this WG is focused specifically on the intersection of the issues facing OGC and W3C members.


The following deliverables are expected to be developed as standards through collaboration with the Open Geospatial Consortium's Geosemantics Domain Working Group, as described below, and to be jointly branded by both standards bodies.

The titles of the deliverables are not final; the two Working Groups will have to decide on the final titles as well as the structures of the documents. The Working Groups may also decide to merge some deliverables into one document or produce several documents that together constitute one of the deliverables.

The superscripts OGC, W3C indicate the standards body whose members have particular expertise in a given area.

Where deliverables build on prior work, any variance developed by the Spatial Data on the Web WG will be backwards compatible with the existing work. The aim is to formalize existing work, not to replace or compete with it.

Subject to its capacity, the working groups may choose to develop additional relevant vocabularies and specifications in response to community demand. For example: a standard method for converting between spatial ontologies; methods to access a subset of a large dataset in terms of its spatial component. Such additional work may be carried out by one or other WG independently of the other.

Best Practice Success Criteria

To advance to Proposed Recommendation, evidence will be adduced that each of the best practices have been followed or recommended in at least two environments.

Vocabulary Success Criteria

To advance to Proposed Recommendation, evidence will be adduced that each term in the vocabulary has been used in multiple environments. This will be most strictly applied to terms developed by the WG, less strictly to terms originating from the prior work whose use or otherwise may not be knowable.


Note: The group will document significant changes from this initial schedule on the group home page.
Deliverable FPWD LC CR PR Rec
Use Cases and Requirements March 2014 June 2015
Best Practices June 2015 December 2015 March 2016 July 2016 September 2016
Time Ontology in OWL June 2015 December 2015 March 2016 July 2016 October 2016
Semantic Sensor Network July 2015 March 2016 June 2016 October 2016 December 2016
Coverage in Linked Data September 2015 March 2016 July 2016 September 2016 December 2016

Timeline View Summary

Dependencies and Liaisons

Relationship with OGC

In collaboration with the W3C, the Open Geosptial Consortium, OGC, will create a sub-working group of the Geosemantics Domain Working Group subject to its usual practice and rules of membership. This will be a RAND-Royalty Free Standards Working Group according to section 3.2.2 of OGC's 2008 Intellectual Property Rights Policy (PDF) to ensure compatibility with W3C's Patent Policy. Formally, each group will have its own charter and operate under the respective organisation's rules of membership, however, the 'two groups' will work together very closely and create a set of common outputs as set out above that are expected to be adopted as standards by both W3C and OGC and to be jointly branded.

As is now common practice, the W3C group will work in public, i.e. it will use a publicly visible mailing list and wiki, and the editor's drafts of its documents will be publicly visible (e.g. on GitHub). To enable write access to these facilities, unless there are specific reasons to the contrary, members of the OGC WG who do not represent W3C member organizations will be granted Invited Expert status, with all obligations and privileges, in the SDWWG but without access to member-only resources.

It is expected that the WG's chairs and editors will represent organizations that are members of both standards bodies.

W3C Groups

As well as collaborating with the OGC's Geosemantics Domain Working Group, the SDWWG will be responsible for liaising with the following W3C groups.

Data on the Web Best Practices Working Group
Coordinate on best practices, especially in areas of potential overlap.
Geolocation API Working Group
The group defining the Level 2 Geolocation API to cover geofencing, and the Device Orientation API.
Annotations WG
Particularly with reference to annotating maps
Internationalization Activity
Ensure that multilinguality concerns are properly reflected in the best practices. The WG should also take note of the work of the Best Practices for Multilingual Linked Open Data Community Group.
Privacy Interest Group
Ensure that the privacy concerns are properly included in the best practices.
Data Activity Coordination Group
Ensure that the WG operates in cooperation with others working in related fields.
RDF Stream Processing
Not directly in scope for the SPWG but relevant to the Web of Things which is in turn highly relevant.

OGC Groups

As well as collaborating with the W3C's SDWWG, the Geosemantics DWG will be responsible for liaising with the following OGC groups.

Geometry DWG
Supporting the spatial ontology conformation to ISO 19107, GeoJSON, GeoJSON-LD.
Coordinate Reference System DWG
Supporting the spatial ontology conformation to ISO 19107, GeoJSON, GeoJSON-LD.
Metadata DWG
Particularly to advice on providing different levels of metadata.
Architecture DWG
Overarching group considering architectural issues to multiple OGC specifications, to support Use Cases and Requirements and advise on RESTful APIs
Temporal DWG
To directly support the Time Ontology in OWL and propose complementary scope, particularly concerning additional Temporal Reference Systems.
Sensor Web Enablement DWG
Support the Semantic Sensor Network Vocabulary
Coverages DWG
In direct relation to the Coverage in Linked Data
Mobile Location Services DWG
Directly relates to the W3C GeoLocation WG
Points of Interest SWG
General support the Spatial data on the Web Best Practices
Directly supporting the Spatial Linked Data on the Web
Simple Features SWG
Supporting the spatial ontology conformation to ISO 19107, GeoJSON, GeoJSON-LD
CRS Well Known Text SWG
Supporting the spatial ontology conformation to ISO 19107, GeoJSON, GeoJSON-LD Naming Authority - advising on the URIs
GeoServices REST SWG
To develop advice on RESTful APIs
RESTful Services Policy SWG
To develop advice on RESTful APIs
Web Coverage Service (WCS) SWG
The group working on web services serving coverages

Other Groups & Projects

SmartOpenData, GeoKnow, MELODIES, DaPaas, InGeoCloudS
A range of EU-funded projects are working in closely related areas, the list above is not exhaustive.
The Strabon platform implements stSPARQL that offer a number of spatial and temporal extension functions.

Furthermore, the Spatial Data on the Web Working Group expects to follow these W3C Recommendations:


To be successful, the Spatial Data on the Web Working Group is expected to have 20 or more active participants for its duration. To get the most out of this work, participants should expect to devote several hours a week; for budgeting purposes, we recommend at least half a day a week. For chairs and document editors the commitment will be higher, say, 1-2 days a week. Participants who follow the work less closely should be aware that if they miss decisions through inattention further discussion of those issues may be ruled out of order. However, most participants follow some areas of discussion more closely than others, and the time needed to stay in good standing therefore varies from week to week. The Working Group will also allocate the necessary resources for building Test Suites for each specification.


This group primarily conducts its work on the @@@public mailing list@@@. Administrative tasks may be conducted in @@@Member-only@@@ communications. (Links to be added if charter approved) Comments on the group's work will be welcome via public-gdw-comments@w3.org [subscribe] [archive]

Information about the group (deliverables, participants, face-to-face meetings, teleconferences, etc.) is available from the Spatial Data on the Web Working Group home page.

Decision Policy

As explained in the Process Document (section 3.3), this group will seek to make decisions when there is consensus. When the Chair puts a question and observes dissent, after due consideration of different opinions, the Chair should record a decision (possibly after a formal vote) and any objections, and move on.

A formal vote should allow for remote asynchronous participation—using, for example, email and/or web-based survey techniques. Any resolution taken in a face-to-face meeting or teleconference is to be considered provisional until 5 working days after the publication of the resolution in draft minutes sent to the group's mailing list.

This charter is written in accordance with Section 3.4, Votes of the W3C Process Document and includes no voting procedures beyond what the Process Document requires.

Patent Policy

This Working Group operates under the W3C Patent Policy (5 February 2004 Version). To promote the widest adoption of Web standards, W3C seeks to issue Recommendations that can be implemented, according to this policy, on a Royalty-Free basis.

This is unaffected by the group's collaboration with the OGC as set out above. However, it is worth noting that OGC process requires that the chairs begin each meeting (virtual or physical) by making a Patent Call. The text of that call is set out in Appendix C of the OGC Intellectual Property Policy Rights Policy. Members of the SDWWG should be mindful of this call.

For more information about disclosure obligations for this group, please see the W3C Patent Policy Implementation.

About this Charter

This charter for the Spatial Data on the Web Working Group has been created according to section 6.2 of the Process Document. In the event of a conflict between this document or the provisions of any charter and the W3C Process, the W3C Process shall take precedence.

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