Data Interoperability

1 Like

I made a first start with this in


The Avatar team’s approach is posted at Common Core Ontology with Linked Data.

We’re renaming our Common User Profile to call it ‘card+,’ since it allows compatible card extensions that all conform to the Common Core Ontologies (CCO).

Since this group seems to have consensus on using FOAF for the Solid Card, we will post a solution soon that is both FOAF and CCO compatible, plus allows compatible extensions.

More will be posted within a week or maybe two.

Jim Schoening


Data Interoperability, Solid, and CardX

August 5th, 2019


We propose CardX, an extended form of the existing Solid card. CardX stores the same information as the existing card format; however, apart from infrastructure data such as storage and account information, the data is mapped using the Common Core Ontologies (CCO)1.

The CCO, which is based on Basic Formal Ontology2 (BFO) provide a rich set of mid and upper ontologies that can fulfill the role of cross-domain information representation. This enables the ability for multiple individuals to share and leverage information relevant to them. It is infinitely extensible and supports querying information at multiple levels so that the degree of exactness vs. generality required by a given use case can be applied3.

While there are several benefits to using the CCO, the most beneficial aspect with regards to data interoperability is the fact that it can be extended in a logically consistent manner. To accomplish this extension, the CCO is accompanied by a rule-guided method. The combination of the CCO and this methodology allows different groups to develop ontologies and still arrive at semantically interoperable models4.

The CCO is compatible with other ontologies, such as FOAF5, already in use by the Solid community. In the coming weeks our team will be releasing tools for working with CardX.

These tools will support three CardX use cases:

  1. A Solid user who would like to use CardX by adding the CardX triples to their existing card.
  2. A Solid developer how wishes to use the CCO while keeping their app available to users of the current Solid card.
  3. A Solid user who wishes to replace their Solid card with the CardX.

These tools include:

  1. CardX Creation App: This app allows a Solid user to populate the fields of their CardX using a number of data sources including their existing card, manual entry into a form, and appropriately mapped RDF files produced by the Facebook data retrieval tool (soon to be released).
  2. CardX-lib: This library provides tools for converting information from the existing card into the CardX format within a developer’s app, as well as for converting the data back into the existing card format for storing changes back to a user’s Solid pod. The inverse functionality will also be supported, allowing developers of currently existing apps to convert data from CardX users to the current card format for use in their apps. Additionally, this library will provide functionality for card/CardX reconciliation for users who choose to maintain both card formats on their pod.

Recently our team launched a calendar app that utilized the CCO to store event data. Today we will be releasing a weather application that, in addition to display a user’s local weather based on their address, will be able to display events previously scheduled for the current day using the calendar app. These apps demonstrate a cross application data use case that show the benefits of using a common, extensible ontology.


Please contact the individuals below with questions or requests for support:

Jason Reynolds (Polaris Alpha), Solid forum ID: JKReynolds
Robert Ganger (CUBRC, Inc.), Solid forum ID: rganger
James Schoening (US Army CCDC C5ISR), Solid forum ID: JimSchoening


1 “CommonCoreOntology,” GitHub. [Online]. Available: [Accessed: 2August-2019].
2 “Basic Formal Ontology (BFO) | Home.” [Online]. Available: [Accessed: 2August-2019].
3 “Data Integration for the Individual using the Solid Platform,” GitHub. [Online]. Available: Integration%. [Accessed: 2-August2019].
4 “Ontology” [Online]. Available: [Accessed: 2-August-2019]
5 “FOAF Vocabulary Specification.” [Online]. Available: [Accessed: 21-May-2019].

@MitziLaszlo @michielbdejong We are currently reviewing how CardX would impact or could benefit current Solid apps as well as confirming it’s alignment with and vcard. Afterward, we will post what we find.

1 Like

Hi @JKReynolds,

Great work! Best to connect with the other panellists on the Data Interoperability Panel.


1 Like

thanks for info :slight_smile:

1 Like