Demonstration and Evaluation of a Fault-Tolerant Input/Output Network

A digital computer input/output data network is evaluated as to its ability to be reconfigured, tested, and managed. The network is topologically more complex than a bus structure, each node being connected to three, rather than two, internodal links. The extra connectivity offers redundancy that can be used to tolerate failures of any kind in links as well as to circumvent paralysis of the system due to an actively malfunctioning node. The software overhead of the network amounts to less than 2K 16-bit words of instructions and data for a moderate size system. The bandwidth overhead is variable depending on the degree of security desired, and can range from several percent to tens of percent.