Estimation of Time-Dependent Coverage
David Powell, Michel Schatkin Cukier, Jean Arlat, Yves Crouzet · 1996
. It is well-known that the dependability that can be achieved by a fault-tolerant system is particularly sensitive to both the asymptotic value of coverage and to the time distribution of coverage. However, most previous work on coverage evaluation by statistical processing of the results of fault-injection experiments has only been concerned with estimating asymptotic coverage. In this paper, we tackle the problem of estimating the parameters of models that also account for coverage latency. After discussing some data sets resulting from fault-injection experiments on practical systems, we propose a series of coverage latency models that might be considered to account for the observed phenomena in a system dependability evaluation. We consider both exponential and non-exponential models, and assess their pertinence by means of a sensitivity study. We confirm previous results that latency can have an extremely important effect on the achievable dependability. We also show that the sha...