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Architecture for the Validation Testing System Software



Katherine C. Morris


This document is part of the National PDES Testbed Report Series and is intended to complement the other reports of the Validation Testing System (VTS) project. Other documents describe the methodology for model validation and software requirements for automating that methodology.

The problem of sharing data has many facets. The need for the capability to share data across multiple enterprises, different hardware platforms, different data storage paradigms and systems, and a variety of network architectures, is growing. The emerging STandard for the Exchange of Product model data (STEP), a project of the International Organization for Standardization (ISO), addresses this need by providing information models, called application protocols, which clearly and unambiguously describe data. The validity of these information models is essential for success in sharing data in a highly automated business environment.

This document describes an architecture for an integrated software environment to support the validations of STEP application protocols. The architecture provides a basis for software development to support the Validation Testing System within the National PDES Testbed. (PDES, Product Data Exchange using STEP, is the U.S. effort in support of the international standard.) The software architecture and the use of object-oriented techniques enables code reusability and system extensibility. The software developed for the VTS can provide the foundations for STEP related systems or software projects requiring general purpose editing tools for structured information.

NIST Interagency/Internal Report (NISTIR) - 4742
Report Number


model variation, PDES, software requirements, STEP, Validation Testing System (VTS)


Morris, K. (1992), Architecture for the Validation Testing System Software, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 12, 2024)
Created January 1, 1992, Updated November 10, 2018