National Archives of the Netherlands (Ministry of Education, Culture and Science)

Dioscuri

The Dioscuri modular emulation project ran from 2005 to 2007. The State Archives Service worked together with the Dutch National Library (Koninklijke Bibliotheek, the KB) to develop an open source emulator that is ‘modular’, so that it can easily be transferred to another host platform (in a ‘portable’ fashion). A so-called Universal Virtual Machine (UVM) runs on existing hardware and software so that the emulator is not dependent upon a specific combination of hardware and operating system. The modular construction reduces the effort required to run the emulator on a different target machine, as modules can be reused and new modules added as and when necessary.
The modular emulator at the heart of the model enables the use of original operating systems and original user software. The emulator consists of separate modules, each of which emulates a specific hardware component such as a CPU, RAM-memory, hard discs, graphics card, etc.
Modules can be reused in different combinations to configure or emulate different computing systems. All modules are stored in a so-called ‘module library’. An emulator specification document describes which modules must be used to produce a given environment. Technicians can then combine and load the required modules to produce the desired emulator ‘on the fly’. The emulator supports 8- and 16-bit operating systems and applications (for DOS and early versions of WINDOWS, up to v3.11).
Dioscuri enables the State Archives Service and the KB to provide access to digital files in their original environments; that is to say, using original operating systems and software applications. This approach helps ensure the integrity and authenticity of digital objects through the years. Unlike migration, emulation is focused not upon the digital object itself but the original environment in which the object was first created and rendered. The goal of emulation is thus also to recreate original environments.