Hierarchical multi-microcomputer systems

Hierarchical multi-microcomputer systems are reviewed, with particular attention given to the complexity of the interconnection structure and to the ability to exchange messages. The assumption of the multiple-instruction multiple-data (MIMD) computational paradigm is followed; autonomous but cooperating tasks execute on different processing units in the system. The overall complexity of the systems is measured with the analysis of the diameter and of the increasing law, which states the number of interconnections against the number of nodes in the system. The various architectures are compared in terms of links load and average internode distance under the uniform reference model of message distribution and of request independence assumption.<>