A Measurement Framework for Evaluating Emulators for Digital Preservation

Accessible emulation is often the method of choice for maintaining digital objects, specifically complex ones such as applications, business processes, or electronic art. However, validating the emulator's ability to faithfully reproduce the original behavior of digital objects is complicated. This article presents an evaluation framework and a set of tests that allow assessment of the degree to which system emulation preserves original characteristics and thus significant properties of digital artifacts. The original system, hardware, and software properties are described. Identical environment is then recreated via emulation. Automated user input is used to eliminate potential confounders. The properties of a rendered form of the object are then extracted automatically or manually either in a target state, a series of states, or as a continuous stream. The concepts described in this article enable preservation planners to evaluate how emulation affects the behavior of digital objects compared to their behavior in the original environment. We also review how these principles can and should be applied to the evaluation of migration and other preservation strategies as a general principle of evaluating the invocation and faithful rendering of digital objects and systems. The article concludes with design requirements for emulators developed for digital preservation tasks.