Diagnosis of t/(t +1)-Diagnosable Systems

  • Authors:
  • A. Das;K. Thulasiraman;V. K. Agarwal

  • Affiliations:
  • -;-;-

  • Venue:
  • SIAM Journal on Computing
  • Year:
  • 1994

Quantified Score

Hi-index 0.00

Visualization

Abstract

A classic PMC (Preparata, Metze, and Chien) multiprocessor system [F. P. Preparata, G. Metze, and R. T. Chien, IEEE Trans. Electr. Comput., EC-16 (1967), pp. 848--854] composed of $n$ units is said to be $t/(t+1)$ diagnosable [A. D. Friedman, A new measure of digital system diagnosis, in Dig. 1975 Int. Symp. Fault-Tolerant Comput., 1975, pp. 167--170] if, given a syndrome (complete collection of test results), the set of faulty units can be isolated to within a set of at most $t+1$ units, assuming that at most $t$ units in the system are faulty. This paper presents a methodology for determining when a unit $v$ can belong to an allowable fault set of cardinality at most $t$. Based on this methodology, for a given syndrome in a $t/(t+1)$-diagnosable system, the authors establish a necessary and sufficient condition for a vertex $v$ to belong to an allowable fault set of cardinality at most $t$ and certain properties of $t/(t+1)$-diagnosable systems. This condition leads to an $O(n^{3.5}) t/(t+1)$-diagnosis algorithm. This $t/(t+1)$-diagnosis algorithm complements the $t/(t+1)$-diagnosability algorithm of Sullivan [The complexity of system-level fault diagnosis and diagnosability, Ph. D. thesis, Yale University, New Haven, CT, 1986].