Beyond micro-kernel design: decoupling modularity and protection in Lipto

It is argued that a modular operating system architecture should provide support for modularity independent of protection domains. Given such support, modules and interfaces can be designed according to sound software engineering principles, without concern for cross-domain invocation costs. The partitioning of modules into domains and across machines becomes a matter of configuration, rather than design. Current micro-kernel-based architectures do not sufficiently address this issue since their communication mechanisms are designed for the nonlocal, i.e., cross-domain, case. An architecture that provides location-transparent binding and access of modules optimized for the local case, thereby decoupling the orthogonal concepts of modularity and protection, is proposed