Buy a License #

RDF SemSpect is a stand-alone server application that requires a commercial license for full functionality. Please send your requirements to licensing@semspect.de.

Please note: We provide licenses free of charge for academic and open data projects. Read the conditions here and get in touch with us at licensing@semspect.de.

The price of the RDF server license is per server instances and depends on the number of concurrent sessions:

There are discounts for additional instances, multi-year licenses and up-front payment.

A session corresponds to a user’s interaction with the software over a certain period of time. No user registration or login is necessary, but users automatically receive a session from a shared pool of sessions (floating user model). A session is assigned if the user actively uses the software via a web browser (different browsers and/or separate browser environments count as different users). After a configurable period of non-use, the session is released again. The acquired number of concurrent users is coded in a license file and is checked by the server instance at runtime.

One server instance refers to one individual deployment of the RDF SemSpect server. One server instance can serve as many databases at the same time as the resources of the host system allow. However, the parallel operation of servers - as backup, for load balancing or hot standby - requires additional licenses.

Limitations of the Free Version #

The free version of RDF SemSpect is free of charge, but has the following limitations:

• No index persistence: RDF SemSpect creates its own compressed indices for each dataset supplied. The indexes are stored on disk to reduce the startup time for each successive run. The free version does not allow pre-generated indexes to be loaded, so index creation must be repeated for each run.

• No multi-session usage: During the runtime of an RDF SemSpect server, only one browser can connect to the server. This means that the first web browser receives the only available session to interact with the server. Every further user or switching to another browser requires a restart of the RDF SemSpect server.

• Session duration limit of 8h: The RDF SemSpect server runs for a maximum of 8 hours. After this time, you must restart the server to reset the session timer. The remaining time of your session is displayed at the bottom right of the status bar in the user interface.

• At most 3 SemSpect classes resp. saved explorations: While SemSpect classes and saved explorations can be deleted or updated any time, users can specify a maximum of 3 SemSpect classes and save a maximum of 3 explorations.

• No SPARQL query access: The display of the SPARQL queries (to retrieve the resources of a group or the contents of a table view) is not available.

• Maximum of 7 groups in an exploration: The total number of groups in an exploration is limited to 7.

• Data download restriction of 10 entries: The CSV download of data in tabular views is limited to a maximum of 10 entries per request.

• No exploration graph image download: The PNG and SVG image download of exploration graphs is not available.

• No data load via URLs: The free version is limited to loading local datasets and does not allow data to be loaded via URLs or the SPARQL HTTP Graph Protocol.

About Academic and Open Data Licenses #

By requesting an academic or open data license, you agree that derivo GmbH may mention your project and/or your group as SemSpect user in its marketing activities.

Moreover, a 15 minutes video interview to collect feedback on your usage of the application will be required for a renewal of the initial 6 months license.

Get in touch with us at licensing@semspect.de.