 
Summary: ABSTRACT
A novel Markov model for the reliability prediction of
faulttolerant nonhomogenous VLSI and WSI multipipe
line arrays is presented. The PEs of the array are assumed
to fail independently (with a constant failure rate) at differ
ent moments and the transition rate between two different
error states is constant. A total system failure is reached
when the number of working pipelines becomes less than a
predetermined number Sm. Thus the reliability of the mul
tipipeline array is defined as the probability of having S(t)
greater than or equal to Sm, where S(t) is the number of
survived pipelines at time t, and Sm is the minimum number
of survived pipelines that is needed for the multipipeline to
be considered in a working condition. In addition to pre
dicting the reliability, the Markov model can be used in
design optimization to determine the best possible design
among multiple alternatives. Several experiments are con
ducted that demonstrate the ability of the proposed Markov
model to predict the reliability and to evaluate various
design alternatives.
