This dissertation supports the claim that information appliances and communication-oriented systems in general require and benefit from novel operating system concepts. The path abstraction and Scout's demultiplexing scheme are just two examples discussed in this dissertation that are novel concepts designed specifically with the needs of information appliances in mind. This is not to say that these concepts are necessarily limited to appliances, or that they would not have been conceived without appliances, but the needs of appliances at least fostered their invention. The ultimate truth of the claim can only be evaluated as a function of the success or failure that information appliances experience in the long term.
The dissertation establishes that paths can be evolved into a fundamental abstraction. In Scout, paths are the only means to communicate, in a controlled fashion, data between an arbitrary module pair. Paths also have been shown to be efficient, general, and useful. The generality of paths derives from the fact that they can be so short that a Scout system can degenerate into a traditional modular system. Such a degenerate system is certainly not optimal with respect to performance or resource management, but it ensures that any modular system can be built with Scout. The two validation studies presented in this dissertation suggest that paths are useful both to optimizing the processing along a path, as well as to ensure proper resource management on a per path basis. Micro- and macro-benchmarks show that paths do not incur undue space or time overhead and often help improving system performance. In other words, Scout paths are efficient and light-weight.