A Fault-tolerant Reconnguration Scheme in the Faulty Star Graph

In this paper, we propose a scheme to identify the maximal fault-free substar-ring. This is the rst result to derive a reconnguration scheme with high processor utilization in the faulty n-star graph. The maximal fault-free substar-ring is connected by a ring of fault-free virtual substars with dilation 3 and maximal length of the ring is n(n ? 1)(n ? 2). Our proposed scheme can tolerate n ? 3 faults such that the processor utilization is n 2 ?2n+3 n 2 ?n. This is a near optimal result since the maximal fault-free substar-ring is constructed by using all of the possible fault-free (n ? 2)-substars. Moreover, our algorithm can still work when number of faults exceeds n ? 3. The simulation results also show that the processor utilization is more than 50% if the number of faults is less than n 2 ?n?1 2 in the n-star graph.