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Application Protocols for Mechanical Parts Production Plan



Chuck Stark


The STandard for the Exchange of Product model data (STEP) is being developed as an international standard. The National PDES Testbed was established at NIST specifically to address the development and testing of STEP, and to serve U.S. industry in its use of the standard.

An Application Protocol (AP) is a specification for a subset of STEP data that can be implemented in an application system. The Application Protocols for Mechanical Parts Production effort will produce an early example of APs being used together in an operational prototype. This effort will develop, fully test, validate, and deliver a set of Application Protocols to the STEP Production Cell application systems which support the following: detailed design, process planning, and numerical-control programming.

This document describes the plan for developing and validating a series of three Application Protocols required as input to the STEP Production Cell. The resultant candidate APs that will be submitted to ISO for inclusion in the standard will have been validated and thoroughly tested prior to their submission.

NIST Interagency/Internal Report (NISTIR) - 4628
Report Number


STEP, standard, test, validate, application systems


Stark, C. (1991), Application Protocols for Mechanical Parts Production Plan, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD (Accessed April 17, 2024)
Created January 1, 1991, Updated October 16, 2008