Open standards are stable, published formats for data and services that are independent of any individual supplier. They are essential for systems and data to be interoperable. Without open standards, open data can realise only a fraction of its value.
Because CKAN is built on open standards, it helps data from different sources work together. It also ensures that users are never “locked in”: data and metadata in CKAN can easily be harvested into a different system.
HTML is the lingua franca of the Web, the language spoken by every web page and browser. Ensuring a site’s HTML validates correctly makes it accessible to the widest possible audience and increases its visibility and usefulness. CKAN outputs pages in in XHTML 1.0. From the release of CKAN 2.0 it will target HTML 5.
REST, or Representational State Transfer, is a standard interface for Web applications. CKAN’s web interface and API are RESTful, leading to increased robustness (for example against network failure), scalability, and interoperability.
CSW, or Catalogue Services for the Web, is a standard defined by the Open Geospatial Consortium for publishing catalogue records for geospatial data. CKAN can harvest CSW data when importing records and includes a CSW server to present a CSW interface to its own data.
The EU INSPIRE Directive aims to create a Europe-wide infrastructure for public sector spatial information. By making spatial data more interoperable, it facilitates unified policies between regions, for example on the environment. To this end it specifies formats and discovery services that public authorities must use for publishing spatial data. CKAN can harvest INSPIRE data and help affected organisations meet their obligations under the directive.
DCAT is a standard vocabulary for describing datasets in data catalogues. By using DCAT, publishers make their data more discoverable and enable applications to combine or search across multiple data catalogues.
CKAN includes native exporting of records in DCAT format, and can harvest DCAT records from other catalogues.
CKAN also respects the schema at spec.datacatalogs.org, which is the result of ongoing discussion on the email@example.com mailing list. It is based on DCAT with some recommendations about usage, and includes a mapping to JSON.