The NASA Space Network (SN), which consists of the geosynchronous Tracking and Data Relay Satellite (TDRS) constellation and its associated ground elements, is a critical national space asset that provides near-continuous, high-bandwidth telemetry, command, and communications services for numerous spacecraft and launch vehicles. The Space Network includes several key ground system elements, one of which is the White Sands Complex Data Interface Service Capability (WDISC). The WDISC has undergone multiple cycles of modification and technology refresh over its lifetime, making test automation an attractive option for reducing system verification and validation cost. This paper considers the implementation of automated testing for the WDISC as a case study in technology sustainment, discusses the principal benefits and challenges of implementing test automation for a legacy system, and presents findings that demonstrate the effectiveness of such automation models.