exff is "exPRESS for free" ... or is it?

exff (pronounced "XF") began life with the goal of enabling the use of ISO STEP standard engineering/industrial information models in a modelling and implementation environment based on the Unified Modeling Language^TM (UML^TM). However, we've decided to broaden its scope based on the advances in the OMG Model Driven Architecture^TM (OMG MDA^TM), OMG SysML, W3C Semantic Web, knowledge-based and information architectures communities.

exff is now a project with the mission of enabling the mixed use of UML-, logic- and EXPRESS-based modelling and implementation tools in an integrated, coordinated environment. It also aims at enabling the population of existing and in-development Architecture Frameworks using these tools. The major business rationale for this goal remains supporting organizations in taking advantage of the ISO STEP information models in other contexts including:

• as the basis for knowledge- and/or rule-based applications such as the Semantic Web,
• as the basis for applications used in the definition of systems of systems, and
• as the basis for UML-driven software systems engineering and systems integration capabilities.

Given the breadth of the new scope, it will take time to evolve this Web site to cover everything. This interim release still has a mix of the old and the new. That also raises the question... Given the new exff scope, do we need a new name? Suggestions are welcome. We will reorganizing the exff site based on focus areas. At the moment, there following are available:

• The exff STEP Support Page,
• The exff Semantic Web Support Pages.

The exff Flyer and exff in 10 Minutes may assist in understanding the original exff intent. The Executive Summary and the STEP Summary for the STEP community will also help.

If you are already familiar with exff, then go to the project status pages or the site map. If you are new to exff, then read on.

Status

Eurostep initiated the project, funded development of the concept and are now seeking funding, partners and/or the contribution of development resources. The exff Project is currently at the stage of making a development proposal. exff will result in a full suite of modelling and implementation tools.

The feasibility of exff has already been shown in three demonstrators.

1. The exff Release 0.1 deliverables allow the use of a UML modeling tool to export and import simple ISO EXPRESS schemas.
2. The exff Release 0.1a deliverables allow the use of a UML or EXPRESS modeling tool to create simple W3C OWL ontologies.
3. The AP233 demonstrator shows the exchange of ISO STEP Systems Engineering requirements data into a UML modeling tool.

Goals

The main exff business goal is to speed the development and deployment of Industrial Data applications.

In the domain of Industrial Data, the ISO EXPRESS data specification language, the eXtensible Markup Language (XML), and the Unified Modeling Language (UML) are three key technologies for the data modeling and software engineering communities.

The exff business goal is to be met by:

1. enabling the re-use of models across many domains, and
2. enabling the use of a variety of modeling and implementation systems across the Industrial Data and traditional software engineering communities.

Approach

The exff technical approach is to extend existing open source, or free, modeling tools and integrated development environments so that they support the interoperability of the key information technologies. Many of these support the Object Management Group standard for model interchange called XML Metadata Interchange (XMI). XMI is the key enabling technology standard for exff.

By using XMI, the exff results will also be easy to apply to the numerous commercial software tools supporting that standard. This benefits organizations, both large and small, requiring interoperability and allows quicker development and deployment of innovative solutions. Figure 1 shows the architecture of exff. exff allows the interchange between EXPRESS, UML and Integrated Development Environment tools as well as directly driving some aspects of implementation itself.

Figure 1 - The exff Architecture

The exff infrastructure will also make existing standard models available to a wider audience by allowing them to be recast into the languages used in other disciplines. Examples of this include:

• logic languages for the Semantic Web (see the white paper),
• EXPRESS for ISO data exchange protocols,
• UML and many programming languages for software engineering,
• SQL DDL for automated generation of relational databases and APIs,
• XML-based languages for Web Services.

Based on the exff infrastructure, domain-specific applications (e.g. Systems Engineering ) can be developed that implement ISO and OMG standards, and that can be harmonized with related standards and/or proprietary solutions in other domains as well.

Based on the exff infrastructure, organizations will also be able to re-use elements of models, standard or not, in their internal development. This will reduce costs and speed implementation.

License

The exff Project is developed under the Common Public License.