Many of you will be familiar with the now ubiquitous Linked Open Data cloud diagram, maintained by Richard Cyganiak. The diagram illustrates efforts to link together many different data sources, from the CIA World Factbook to DBpedia, a structured database of information extracted from Wikipedia. It looks like this:

We’re very pleased that the diagram’s maintainers, Anja Jentzsch, Richard Cyganiak, and Chris Bizer, have decided to use CKAN to maintain a registry of information about the datasets, from which the diagram will be automatically updated. They have put out a call for up to date information about datasets included in the diagram until next Wednesday 8th September.

From their announcement:

We are in the process of drawing the next version of the LOD cloud diagram. This time it is likely to contain around 180 datasets altogether having a size of around 20 billion RDF triples.

For drawing the next version of the LOD cloud, we have started to collect meta-information about the datasets to be included on CKAN, a registry of open data and content packages provided by the Open Knowledge Foundation.

The list of datasets about which we have already collected information is be found here:

In addition to basic meta-information about a dataset such as its size and the number of links pointing at other datasets, we also collect additional meta-information about the license of the dataset, alternative access options like SPARQL endpoints or dataset dumps, and whether there exist a voiD description of the dataset or a Semantic Web Sitemap.

So if your dataset is not listed yet and you want to have it included into the next version of the LOD cloud, please add it to CKAN until next Wednesday (September 8th, 2010).

Also, if we have collected wrong information about your dataset or if your dataset is only partially described up till now, it would be great if you could add the missing information.

Guidelines about how to add datasets to CKAN as well as about the tags that we are using to annotate the datasets are found here:

We thank all contributors in advance for their input and help, which hopefully will allow us to draw the next version of the LOD cloud as accurate as possible.