Assuring quality and reliability of complex electronic systems: hardware and software

Transients’ effects on the reliability of programmable electronics

“…The device failure rate model follows the Weibull distribution in its early life and is followed by a very long, useful life of constant failure rate. Typically the constant failure rate ranges from a few ppb to a few hundred ppb [1]. Thus, electronic hardware is rarely responsible for failures, even for very complex computer systems [2].…”

“…The proliferation of programmable electronics gives rise to concern over the risks of software. To contain the risks of software, structured programming, software quality assurance and fault-tolerance techniques are increasingly being used [1,3]. In a survey of well-debugged programs, MTTF ranging from 1.6 years to 5,000 years was reported [4].…”

The reliability of ring networks

“…In figure 5, we show the equivalent ring (Homo-Ring), with back-up links and all links have identical reliability (0.8). The proof that figure 5 have reliability values identical to those in figure 4 is easy and therefore, we leave it for the interested reader.…”

“…Unlike equation 2, and, for fixed S and L, the reliability given by equation 5 is not unique. This situation is due to the different ways back-up links can be distributed.…”

“…In sections [2][3][4][5] we review some of the results given in [l,]. The modeling of heterogeneous links using back-up links will be the subject of section 6.…”