A systems engineering view of TPS rehosting

The TPS test design process results in UUT detailed test strategy that is independent of its eventual implementation in source code or on a specific ATS. It is test strategy, not source code, that embodies the critical metrics of UUT fault detection and isolation. Source code implementation is the first step in a design chain that finally results in signal-information flow across the test interface. This SI flow is the physical realization of test design. The objective of TPS rehosting is usually preservation of proven legacy test design, but it should also seek to preserve legacy SI flow to avoid the subtle, and often difficult, problems caused by rehosting to the new ATS. These problems can be exacerbated by inability of the original source code to describe what is happening at the UUT test interface, and by the repeated and characteristic need to choose between equivalent performance of, and incidental or substantive enhancements to, the rehosted TPS.