Efficiency of local self-diagnosing in computing systems with circulant diagnostic structure

Diagnosing of computing systems (CS) is examined under conditions of the $t$-multiple faults and test outcomes corresponding to the known PMC-model. A circulant graph with the nodes of degree $t$ is used as the diagnostic structure. In the paper we investigate the opportunity to determine a technical state of each module of the CS using results of testing only those modules which have with it physical connections (local $t$-diagnosing). Possibility of local diagnosing is investigated under conditions when the rules early entered by us provide completeness of diagnosing only at the expense of labourconsuming additional testing of modules. The conditions of the authentic identification of the CS module state on the basis of redundancy among the test outcomes used at the comparative analysis for the determination of the module state are deduced. It is shown that redundancy in the elements for the comparative analysis reduces level in redundancy on number of the additional tests or even excludes the additional testing fully. Conditions at which redundancy of the elements for the comparative analysis are sufficient for maintenance local $t$-diagnosability of the system are proved.