Rescaling reliability bounds for a new operational profile

ABSTRACT

One of the main problems with reliability testing and prediction is that the result is specific to a particular operational profile. This paper extends an earlier reliability theory for computing a worst case reliability bound. The extended theory derives a re-scaled reliability bound based on the change in execution rates of the code segments in the program. In some cases it is possible to derive a maximum failure rate bound that applies to any change in the profile. It also predicts that (in principle) a "fair" test profile can be derived where the reliability bounds are relatively insensitive to the operational profile. In addition the theory allows unit and module test coverage measures to be incorporated into an operational reliability bound prediction. The implications of the theory are discussed, and the theory is evaluated by applying it to two example programs with known faults.

REFERENCES

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INDEX TERMS

Primary Classification:
  D. Software
  D.2 SOFTWARE ENGINEERING
      D.2.4 Software/Program Verification

Additional Classification:
  D. Software
  D.2 SOFTWARE ENGINEERING
      D.2.5 Testing and Debugging

General Terms:
Experimentation, Reliability, Theory

Keywords:
operational profile, operational reliability testing, worst case bounds.