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This is the first technical report from The Archons project, which is performing research in the science and engineering of 'distributed computers'. By this we mean a computer having highly decentralized (e.g., consensus) resource management at every level of abstraction from the executive down. This report provides a snapshot of several incomplete, ongoing investigations: decentralized synchronization; the requirements for simulation of decentralized resource management algorithms; and the facilities to be provided by a decentralized executive. We begin with a summary of our views on decentralized resource management and control, and the implications of physical communications on control (especially at the executive level). Then we briefly survey several other distributed system projects. This brings the Archons project into closer focus, as their orientations and objectives are considerably different from ours. Synchronization (the induction of a common, consistent ordering on events) is the essence of decentralized control. New concepts and techniques are required to achieve synchronization in distributed computers without reliance on any decentralized entity such as a semaphore, monitor, sequencer, or bus arbiter.

This paper introduces a framework for studying the interactions of autonomous system components and the design of the connectivity structure in Systems of Systems (SoSs). This framework, which uses complex network models, is also used to study the connectivity structure's impact on resource management. We discuss resource sharing as a mechanism that adds a level of flexibility to distributed systems and describe the connectivity structures that enhance components' access to the resources available within the system. The framework introduced in this paper explicitly incorporates costs of connection and the benefits that are received by direct and indirect access to resources and provides measures of the optimality of connectivity structures. We discuss central and a distributed schemes that, respectively, represent systems in which a central planner determines the connectivity structure and systems in which distributed components are allowed to add and sever connections to improve their own resource access. Furthermore, we identify optimal connectivity structures for systems with various heterogeneity conditions.