Modelling Software Operational Reliability
under Partition Testing
Yinong Chen
Department of Computer Science
University of the Witwatersrand, Johannesburg
2050 Wits
SOUTH AFRICA
email: yinong@cs.wits.ac.za
fax: +27 - 11- 339 7965
tel.: +27 - 11- 716 3304
Full FTCS-28 Paper in Postscript File
Abstract
Operational reliability of programs depends upon many factors imposed
by design, testing, and operation of programs. In the testing stage,
the main imperfect factors which can affect operational reliability
are faults, testing time, fault correction, testing profile and
operation profile. The modelling process proposed in this paper
takes all these factors into account. It consists of two testing
stages and one operational stage. In the testing stages, partition
testing is used to evaluate the reliability growth. Based on the
profile coverage between testing and operational profiles, a method
is found to partition the input domain, so that the testing profile
can follow the given operational profile of a program. In the
operational stage, the reliability model uses the remaining faults
from the testing stages as the source of unreliability. Different
manifestations of faults in testing and operational stages, due to
different testing and operational profile, are considered. As an
application of the model, the reliability sensitivity to the imperfect
profile coverage is studied. The analytical results agree with the
experimental results from other researchers.
A large program example is tested by use of this model and results
are compared with existing work.
Keywords -- reliability growth, operational reliability,
profile coverage, software fault model.