Domains and Datasets

What is a Domain?

A Domain is a category that contains entities that are closely related. In the Open Data Hub, each domain roughly identifies one social or economical category; the domains intended as sources for data served by the Open Data Hub are depicted at the bottom of Figure 1.

Currently, the domains that can be accessed through the Open Data Hub are:

Mobility , this domain contains data about public transportation, parkings, charging station, and so on.
Tourism: data about events, accomodations, points of interest, and so on.
Other domain: a special category that encompasses domains that do not fall in any of the above category.

Each domain is composed by datasets, each of which contains data that provide useful information for the domain.

It is important to note that there is no clear separation between two domains. For example, data about public transportation belong to the Mobility domain, but are also useful for the Tourism domain.

The goal of the Open Data Hub project is to make available datasets containing data about the European ecosystem, to allow third parties to develop novel applications on top of them, consuming the exposed data. These applications may range from a simple processing of datasets to extract statistical data and to display the result in different graphic formats like pie-charts, to far more complex applications that combine data from different datasets and correlate them in some useful way.

As seen in Figure 1, data originate from different domains (Mobility, Tourism, and so on); they are gathered from sensors and packed together by Data Providers. Sensors can be for example GPS devices installed on buses that send their real-time geographic position or a small electronic device on a plug of an e-charging station that checks the if the plug is being used or not, to let people know that the charging outlet is available.

Datasets are accessible through a REST API, the URL of each endpoint is given along with other information in the description of each dataset, see the lists of datasets in the remainder of this section.

Data Providers

A Data Provider is any entity that shares their Open Data with the Open Data Hub project, allowing their free reuse (ideally under a free licence like or ). Data can be picked up by any third-party to build their application. These entities can be private companies or enterprises, public bodies, and even private citizen.

The updated list of Data Providers that contribute to the Open Data Hub is available on the Open Data Hub’s home page: https://opendatahub.com/community/

Datasets, Open Data, and Licenses

The resources that are part of the Open Data Hub Project are subject to different licenses, which are described in section Licenses for Open Data Hub resources. Derivative material built using Open Data Hub material is also subjected to different licenses, depending on its purpose, as shown in Figure 3.

_images/FLOSS-LM.png — Figure 3 Licenses for the Open Data Hub and derivative material.

A large part of the Open Data Hub resources is represented by the datasets. While some of datasets have been provided for testing purposes or for internal use only, most of them are made of open Data only.

The goal of the Open Data Hub project is to expose only Open Data and the Open Data Hub team members always suggest to use a license to Data Providers releasing datasets, it is not yet possible for the Open Data Hub team to guarantee the availability as Open Data of all the data in the datasets, because the data licensing and its distribution rights are decided by the copyright holder of each dataset.

Since some of the datasets may contain data that can not be distributed by the Open Data Hub team under an open licence like, e.g., or , a user will be able to retrieve from each dataset only those data that are distributed as Open Data. The response to a query is in JSON format (although CSV output can be forced) and is always licensed as Open Data. However, the response may include resources like links to web pages, streams, or images that are subject to a different, even proprietary, licence. For more information about this topic, there is a dedicated section.

The FLOSS four freedoms

The four essential freedoms are the four basic principle to which a software program must comply to be defined free software. As stated on the What is free software? web page (on which you can find a lot more information and details), they are:

Freedom 0

The freedom to run the program as you wish, for any purpose

Freedom 1

The freedom to study how the program works, and change it so it does your computing as you wish. Access to the source code is a precondition for this.

Freedom 2

The freedom to redistribute copies of the program so you can help others.

Freedom 3

The freedom to distribute copies of your modified versions to others. By doing this you can give the whole community a chance to benefit from your changes. Access to the source code is a precondition for this.

Licenses for Open Data Hub resources

The Open Data Hub Project processes dataset, possibly supplied by third-party sources (i.e., Data Providers), which may contain closed data; however, only Open Data are returned to the users’ queries.

According to the main goal of the Open Data Hub Project, we have defined licenses for its different components and we use badges across the documentation for a better visibility. As a rule of thumb, we try to do our best to deliver Open Data, by developing Free/Open Source software that is publicly available on github, and by using an Open Standard for the API used to access data.

These licenses are applied to the Open Data Hub components:

All the software released within the Open Data Hub is Free software and complies with the GPLv3 license. Code repositories can be found at https://github.com/noi-techpark.
The Datasets currently expose Open Data that are in the public domain, so they are released as CC0.

_images/DAC-LM.png — Figure 4 Creative Common Licenses and derivative material.

License of the JSON Responses

Whenever you query the data in the tourism domain of the Open Data Hub, the snippet that you retrieve always includes a block of information called LicenseInfo, similar to the following one:

{
   "LicenseInfo": {
     "Author": "",
       "License": "CC0",
       "ClosedData": false,
       "LicenseHolder": "https://www.lts.it"
   }
}

The highlighted line shows a licence, which in this case is CC0, i.e., public domain and therefore freely reusable.

This block is always included as a child node within a JSON record that starts with an ID and a number of additional information, which may include also hyperlinks to resources that are external to the Open Data Hub, like in the following snippet–shortened for the sake of simplicity, which refers to a webcam and contains a link to an external provider where to find actual resources (e.g., streams and images) from that webcam.

{
  "Id": "D3659E1F111C4CDB2EC19F8FC95118B7",
  "Active": true,
  "Streamurl": null,
  "Webcamurl": "https://webtv.feratel.com/webtv/?&pg=5EB12424-7C2D-428A-BEFF-0C9140CD772F&design=v3&cam=6323&c1=0",
  "LicenseInfo": {
    "Author": "",
    "License": "CC0",
    "ClosedData": false,
    "LicenseHolder": "https://www.lts.it"
  }
}

Whenever hyperlinks like the one shown in line 5 above appear, it must not be implied that the license mentioned in the LicenseInfo block (again, CC0) is applied to them: everything contained in that link may be covered by a different licence.

Indeed, the Licence mentioned in LicenseInfo nodes refer only to content of the parent node–i.e., the one that starts with “Id”, not to the content of any of the other children nodes, including Streamurl and Webcamurl.

Datasets

The list of datasets and all the information associated with them have been moved to the Open Data Hub main web site. https://opendatahub.com/datasets/

To access the dataset, please refer to the How to Access Mobility Data With API v2 and How to access Tourism Data? howtos, which helps you getting started in retrieving data from the Mobility and Tourism datasets, and to the other howtos are available in the dedicated section.

Technical Information for Mobility Dataset and Technical Information for Tourism Dataset are still available in this documentation portal.