Locating and detecting arrays for interaction faults

Abstract

The identification of interaction faults in component-based systems has focussed on indicating the presence of faults, rather than their location and magnitude. While this is a valuable step in screening a system for interaction faults prior to its release, it provides little information to assist in the correction of such faults. Consequently tests to reveal the location of interaction faults are of interest. The problem of nonadaptive location of interaction faults is formalized under the hypothesis that the system contains (at most) some number d of faults, each involving (at most) some number t of interacting factors. Restrictions on the number and size of the putative faults lead to numerous variants of the basic problem. The relationships between this class of problems and interaction testing using covering arrays to indicate the presence of faults, designed experiments to measure and model faults, and combinatorial group testing to locate faults in a more general testing scenario, are all examined. While each has some definite similarities with the fault location problems for componentbased systems, each has some striking differences as well. In this paper, we formulate the combinatorial problems for locating and detecting arrays to undertake interaction fault location. Necessary conditions for existence are established, and using a close connection to covering arrays, asymptotic bounds on the size of minimal locating and detecting arrays are established.

Screening interacting factors in a wireless network testbed using locating arrays

“…A (d, t)-locating array [9] on k factors is an N × k array such that, for every set of d distinct t-way interactions, the set of tests containing at least one of those interactions is not the same as the set of tests obtained from a different set of d distinct t-way interactions. Interactions may appear in different numbers of tests; an interaction has higher coverage if it appears in more tests.…”

“…A locating array permits locating the set of t-way interactions that cause the response of pass, provided there are at most d of them. A (d, t)-detecting array [9] is similar, but requires that the responses for a set of d t-way interactions rule out each t-way interaction not in the set of d. Reconstruction of the set of t-way interactions yielding a given set of responses is not known to be polynomial-time computable using locating arrays; when detecting arrays are used, efficient reconstruction is possible.…”

“…As one means of reduction, locating arrays (LAs) have been defined [9]. For a set of factors each taking on a number of levels, an LA permits the identification of a small number of significant interactions among few (factor, level) combinations.…”

Locating Minimal Fault Interaction in Combinatorial Testing

“…For nonadaptive methods, the generation of additional test cases does not rely on the running result of original test cases. Colbourn and McClary [8] present a nonadaptive method named Locating and Detecting Arrays (LDA). Based on basic known information such as parameters' number, values, and faults' number, the method applies -way Locating and Detecting Array to locate faults in software system.…”

“…case 0: (8) if ( < 1‖ > 2) (9) (10) //should be: + = ( − )/( + 2); (11) = ( − )/( + 2); (12) else (13) = /( + 2); (14) break; (15) bug of foo; meanwhile, the state of foo is different from its correct prototype. Therefore, the minimal fault interaction set is {{ .0, .0}, { .0, .3}}.…”