GIS Standards

What are GIS standards?

GIS standards are recommended practices to facilitate developing, sharing and using GIS data, GIS software and GIS services. When you look for GIS standards, you actually mean geospatial standards, where GIS is a part of. Geospatial standards concern the use of any geographic information.

Normally any standard is a technical document intended for use as a rule, guideline or definition for common and repeated use. They might include requirements and recommendations for products, systems, processes or services. They possibly describe measurements, test methods or establish common terminologies. A GIS standard is a technical document designed to use for operating with geospatial data.

Why do we need GIS standards?

Standards are necessary to reduce misunderstandings. GIS Standards are essential to harmonize technical specifications for developers, business partners and users. Standards help to optimize operations and improve quality. Geospatial standards increases the compatibility of components, products and services. So international standards facilitate international trade and can open up global markets.

An effective access to web-based geospatial information depends on GIS standards that cut down on time to find geospatial information, to combine diverse information layers and share spatial information on remote servers. So geospatial standards can enhance performance considerably.

There are more than 100 existing geospatial standards including data formats, metadata and services.

GIS standards for data formats

GIS software and GIS services should have the ability to read and write various established data formats. GIS applications should use data format standards to store geospatial data in a common format. You should be able to transfer data from system to system via extract. You may need to transform and load tools for data validation, migration and distribution.

Supported data formats are for example:

  • KML (Keyhole Markup Language) Express geographic data, labels, and symbology in 2D and 3D for web map and globes.
  • GPKG (GeoPackage) Defined by the Open Geospatial Consortium, is GeoPackage an open, non-proprietary, platform-independent and standards-based data format for geographic information systems.
  • AIXM ( Aeronautical Information Exchange Model) The AIXM is a global standard for digital aeronautical data.
  • IHO S-57/ENC (Electronic Nautical Charts) A global standard for electronic navigational charts and marine environments defined by the International Hydrographic Organisation.

GIS standards for metadata

Metadata are data that provides information about other data. Metadata offer a simple way to understand geospatial data. Metadata standards give a structure for creating and organizing metadata such as consistent terminology for catalogs and global search.

Common geographic metadata standards are:

  • ISO 19115: It is a metadata standard whitch defines how to describe geographical information and associated services, including contents, spatial-temporal purchases, data quality, access and rights to use. It is preserved by the ISO/TC 211 committee.
  • CSDGM (Content Standard for Digital Geospatial Metadata) defined by the Federal Geographic Data Committee (FGDC). It is a widely-used, but no longer current standard specifying the information content for a set of digital geospatial data. In September 2010 the FGDC endorsed ISO 19115 and began to confirm federal agencies to transition to ISO metadata.

GIS standards for GIS services

Standards for GIS services are used to transfer (spatial) data smoothly via the web or provide remote access to (spatial) data stored on a web server. They enable users to interact with data, generally through simple web clients, on a live and real-time basis. This contains viewing maps, accessing and querying data, running analyses, and downloading (spatial) data.

Supported services are for example:

  • WMS: Web Map Service for sharing maps across the web.
  • WFS: Web Feature Service for sharing feature data across the web for direct access to geospatial data.
  • WMTS: Web Map Tile Service for sharing pre-cached map tiles across the web for use as basemaps.
  • WPS: Web Processing Service for sharing geoprocessing services across the web for performing dynamic geospatial analytics.
  • WCS: Web Coverage Service for sharing geospatial data stored and managed as a coverage across the web.
  • CSW: Catalog Service for the Web for sharing geospatial information, typically metadata, stored in XML across the web.

Federal agencies are prescribed to use specific endorsed GIS standards. Non-Federal organisations are not required to use them, except they are doing business with Federal agencies. But they are well advised to use standards to support data sharing, integration and interoperability.

Who develops GIS standards?

There are diverse standard organisations who develop new standards and update established ones.

For example:

  • the FGDC – Federal Geographic Data Committee and
  • the OGC – Open Geospatial Consortium.

The standards of this organisations are free of charge but copyrighted.

You have to pay for standards from organisations like

  • ANSI – American National Standards Institute,
  • ISO – International Organization for Standardization,
  • IEC – International Electrotechnical Commission,
  • ASTM – American Society for Testing and Materials,
  • IHO – International Hydrographic Organisation,
  • ASPRS – American Society for Photogrammetry and Remote Sensing.

The reason, why you have to pay for these standards is, that the sales of standards provide support for standards development, support for standards users, intellectual property and commercial value issues, and electronic dissemination.

How are GIS standards developed?

GIS standards are developed in the same way like other common standards. They are developed through sharing knowledge. Diverse technical experts who are nominated by interested parties and stakeholders are building consensus.

Various standards processes often share these important steps:

  • Create a proposal for a new (GIS) standards project
  • Review the proposal
  • Create a working draft for the project
  • Create a committee draft once the (GIS) project team comes to an consensus
  • Issue the draft for wider review and comment
  • Resolve the comments
  • Prepare a final draft based on the resolution of comments
  • Obtain an approval for the final draft for the publication of the new (GIS) standard

(GIS) Standards processes are often iterative until a new standard finally is developed.