Introduction to O-DEF™: The Open Group Open Data Element Framework


The Semantic Interoperability Work Group is producing deliverables that prove semantic interoperability is real today, and is demonstrating how they can add business value.

One of these deliverables is O-DEF™, the Open Data Element Framework, which supersedes and replaces the former UDEF framework. Here’s an introduction to the O-DEF standard by its lead author, Ron Schuldt.


The Need for a Common Language

During the ‘1st Platform’ era, enterprise applications hosted on a mainframe conformed to a centralized data dictionary, and consequently shared a common vocabulary. However, as enterprise applications migrated to distributed servers in the ‘2nd Platform’ era, the applications became increasingly autonomous and the link to a common vocabulary was broken. In most cases, this connection is still missing, but among the notable exceptions are tightly regulated organizations, such as banks, which have developed a widely adopted standard vocabulary (SWIFT) in order to meet the need to exchange data with other banks across the globe.

The data held within applications are among the most important assets of any enterprise. If the enterprise is large enough to require multiple applications, the challenge to manage those data assets becomes more complex as the number of applications rises. At the same time, the need to integrate and reuse those assets increases.

If the only way to connect the various applications is by means of unique, hand-coded interfaces, then the enterprise will struggle, as the development and maintenance of these interfaces will greatly increase the cost and complexity of managing the application landscape. A better solution to this problem would be to adopt a common data language to mediate between the applications, and this is where the O-DEF standard comes in.


The Open Data Element Framework (O-DEF)

The most recent version of the O-DEF standard, O-DEF™, the Open Data Element Framework, Version 3.0, was published by The Open Group in May 2022 to help resolve the need for a universal vocabulary across applications. In addition to minor editorial updates, the following changes have been made in Version 3.0:

  • The term “classification” was replaced with “categorization” throughout
  • A new table of Role Classes was introduced
  • Additional properties (i.e., characteristic applicable to all members of an object class) were added
  • A new Fundamental Enterprise Data Element was added

The O-DEF standard aids interoperability by enabling basic units of data to be classified, using specific object class and property codes, so that equivalences and similarities between the data can be easily determined. The O-DEF standard also incorporates codes from existing international standards; for example, the ‘product’ codes in the O-DEF standard are drawn from the United Nations Standard Products and Services Codes (UNSPSC). Originally developed by the United Nations Development Programme in 1998 to facilitate the delivery of supplies to developing countries and aid to disaster zones, the UNSPC is essentially a list that describes tens of thousands of products and services, and ascribes a unique code to each.

The O-DEF body of work continues to evolve, and over the last two years other international standards have been adopted as plugins, extending the vocabulary of codes in the standard to include types of units of measure, currency, date, and industrial classification.


Benefits of the O-DEF Standard

The comprehensive index of terms now included in the O-DEF standard make it possible for practitioners to assign just about any data element with a name and language-neutral numeric identifier. This ability to represent the same concept across languages makes the O-DEF standard ideal for international communication.

Also, since the index is a federated collection of a core and plugins, it is potentially infinitely extensible: A plugin could be developed by a standards organization, by a body of specialists in a particular area, by a user enterprise, or by a group of user enterprises. This built-in flexibility allows for future integration of the O-DEF standard with independently developed vocabulary standards in order to accommodate specialized objects or concepts.

Some simple examples of O-DEF identifier codes are shown in the table below:



Since the O-DEF identifiers are so compact, they reduce bandwidth in data transfer. This decreases latency and enables even smaller devices to exchange a lot of information, making it ideal for IoT and mobile applications.

Taken together, the O-DEF standard is an elegant, extensible, open standard, which greatly simplifies the development of interface software and contributes to improved management and organization of data.


About The Open Group

The Open Group is a global consortium that enables the achievement of business objectives through technology standards. With more than 870 member organizations, we have a diverse membership that spans all sectors of the technology community – customers, systems and solutions suppliers, tool vendors, integrators and consultants, as well as academics and researchers.

Contact og_odef_info@opegroup.org for more information about the O-DEF™ standard and how to get involved in its evolution.

Contact og_semantic_io_info@opengroup.org for more information about The Open Group Semantic Interoperability Work Group, and how to get involved in achieving its mission to enable semantic interoperability on a global scale, by fostering the development and take-up of vendor-neutral semantic interoperability standards, best practices, and technologies.