50 Years of Isolation

The traditional means for isolating applications from each other is via the use of operating system provided "process" abstraction facilities. However, as applications now consist of multiple fine-grained, independent and separately acquired components, the traditional process abstraction model is proving to be insufficient in ensuring this isolation. Statistics indicate that a high percentage of software failure occurs due to propagation of component failures. These observations are further bolstered by the attempts by modern Internet browser application developers, for example, to adopt multi-process architectures in order to increase robustness. Therefore, a fresh look at the available options for isolating program components is necessary and this paper provides an overview of previous activity and current research in the area.