Interoperability Testing

Loop test. An IGES file from System A is written from and imported back into System A (figure 1). Always perform a loop test when you plan to archive 3D models in an IGES format created by your current CAD system. Be sure to test whether newer versions of your CAD system can import IGES data created with earlier versions.

End-to-end test. Import an IGES file from System A into System B (figure 2). This tests the ability of System B to import IGES entity types created by System A. This tests only the single direction of data flow from System A to System B. Round-trip test. Import an IGES file from System A into System B, then export it from System B back into System A (figure 3, p. 28). Then perform the same test with data that originates in System B. This best simulates the actual sharing of CAD data between two different systems.

Preparation. Before your test, assemble the following resources:

• Access to at least one sending CAD system and its export IGES translator and documentation.
• Access to a different receiving CAD system and its importing IGES translator. If this is not possible, contact someone with direct access to a different receiving system to review all aspects of the tests.
• Become familiar with the printers, plotters, and IGES translator commands and options of both the sending and receiving systems. Also keep these test tips in mind:
• Narrow your tests to those entity types that directly affect your design tasks.
• Before you begin testing, compare the entity maps of the sending and receiving systems to unearth entity types that are not directly supported by both systems.
• Determine how you plan to use the IGES data. For example, when you exchange visual images for technical documentation, you can map to simpler forms, such as spline curves to arc segments. On the other hand, when you exchange complex surface data for machining, mapping curve and surface entities to simpler forms is likely unacceptable. Once you complete your tests, perform the following steps to analyze the results:
• Verify that the IGES data is valid (an ASCII text file of greater than zero length), that it transfers properly, and that the receiving system began initial processing of the file without gross errors.
• Review the export and import error logs. If you are unsure where the log files are, search the online help for log files or error logs. If you still can’t find them, ask your application vendor. These logs are very important.
• Look for entities that either one of the systems had trouble processing. Visually compare the plot files from both systems.

Judge the results
From your analysis of the results, you must determine the degree of success. This history will improve future transfers and tests. If your company allows it, share this information with your application vendors and transfer partners.

You may need to perform interoperability testing a number of times with the same systems. Each test brings to light adjustments you need to make in either the IGES setting options or your entity selection and construction methods. The goal of each test is to improve on the last test until you achieve the results you need. Good luck!