Research on Fault Tolerance

• Highly Fault-Tolerant Parallel Computation
  When the function of a processor is critical, it is common to use three in place of the one so that even if one fails, its instructions will be overridden by the other two. Similarly, one could protect against the failure of k processors by following the instructions of a majority of 2k+1. But, what if these processors are components of a large parallel machine? Is it necessary to replicate each processor 2k+1 times to insure against the loss of any k? We show that, in many cases, one can do better.

• Fault diagnosis in a small constant number of parallel testing rounds
  Assume that processors can be used to test whether others are faulty, we show how to find the faulty ones provided that a strict majority function correctly.