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The NIST EXPRESS Server: Usage and Implementation



Don E. Libes


The National Institute of Standards and Technology (NIST) has built numerous software toolkits and applications for manipulating STEP and EXPRESS data. The NIST EXPRESS Server is a computational facility at NIST, which provides the ability to run toolkit-based applications remotely without installing them locally. EXPRESS Schemas and other data files are e-mailed to the server. The server runs the requested applications on the files and returns any diagnostics or output, also by e-mail. Applications requiring interaction can either be returned via e-mail so that they can be run locally, or run remotely by telnet or rlogin across the Internet. Access to the EXPRESS Server is available at zero cost to anyone who can send e-mail. No initial registration is required. Use is anonymous by default, however it is possible to use the server as a collaborative testbed in which case results can be immediately shared with other server users. The server is capable of restricting file access to one user or a subset of users. It is also possible to make files publicly available. The server maintains many STEP-related standards and draft standards for public access. Machine-processable standards such as STEP schemas can be incorporated automatically when processing user files. The server dramatically lowers the traditional start-up cost and manpower required to obtain and install STEP and EXPRESS tools as well as the continuing support costs to upgrade and maintain the software, by leveraging NIST research, software support and installation, and computing facilities. The server enables people to experiment or demonstrate STEP without a significant investment of time and money, allowing them to build experience and make informed decisions about their future needs for STEP.
NIST Interagency/Internal Report (NISTIR) - 5323
Report Number


computational facility, EXPRESS schemas, EXPRESS Server, PDES, STEP, toolkit


Libes, D. (1994), The NIST EXPRESS Server: Usage and Implementation, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed February 27, 2024)
Created January 1, 1994, Updated October 16, 2008