Dealing with Inexactnesss in Fault-Tolerant Systems

这项研究的短期目标是设计和评估容错系统中数值不准确问题的一般解决方案。长期目标是了解如何最好地利用并行和分布式系统中的固有冗余来提供高度可靠的多计算环境。不精确度的来源包括舍入误差、噪声、量化误差、软件多样性、不确定性、异质性和冗余传感器。不精确问题包括近似一致性、不精确一致性、时钟同步、传感器融合、软件多样性和投票不精确。在这个项目中，将开发处理并行和分布式系统中的不精确度的新的解决技术，并将研究研究不精确度问题的统一方法。将对项目中开发的技术进行分析评估，并在测试的工作站网络中进行评估。这项研究有望带来更有效和更强大的技术来处理容错系统中的不精确性。这些技术的效果将是提高最终结果的精度，降低冗余的通信开销，并提高整体系统的可靠性。

The short-term objectives of this research are to design and evaluate general solutions to the problem of inexactness of values in fault-tolerant systems. The long-term goals are to understand the ways in which inherent redundancy in parallel and distributed systems can best be exploited to provide highly dependable multicomputing environments. Sources of inexactness include round-off error, noise, quantization error, diverse software, non-determinism, heterogeneity, and redundant sensors. Inexactness problems include approximate agreement, inexact agreement, clock synchronization, sensor fusion, diverse software, and inexact voting. In this project, new solution techniques for dealing with inexactness in parallel and distributed systems will be developed, and a unifying methodology for studying inexactness problems will be investigated. Techniques developed in the project will be evaluated analytically and in a network of workstations testbed. This research is expected to lead to more efficient and more powerful techniques for dealing with inexactness in fault-tolerant systems. The effect of these techniques will be increased precision of final results, lower communication overhead for redundancy, and increased overall system reliability.