In the past, if you needed a functional test system you had to choose between a complete custom solution — typically integrated by a local system integrator — or a standard, off-the-shelf applicationcentered system, typically delivered by an instrument vendor. Building custom solutions often involved major engineering effort and big expenditures, and the systems were sometimes hard to support and difficult to adapt for testing new products. The standard, application-centered systems often lacked flexibility and frequently relied on proprietary standards or software.