Colin Perkins
DPhil thesis,
University of York,
September 1996.
The reliability modelling and analysis of real-time, fault-tolerant,
embedded systems is considered. It is shown that many existing
reliability modelling techniques are inadequate for this task, since
they model only the overall system reliability, whilst the timing
properties of the system are either neglected, or reduced to simple
metrics. A new reliability model is derived, which permits the
modelling of both overall system reliability, and the probability
distribution of system completion and failure times. This model is
based on a set of high level system attributes, which it is expected
may be estimated from experimental data. The model is applied to the
study of recovery block systems, and it is shown that the results
obtained are compatible with, and extend, a number of other system
reliability models. The thesis concludes with a discussion of the
application of more detailed timing information to the scheduling of
safety-critical real-time systems. It is shown that the additional
timing information available with models such as that developed herein,
allows designers to make more informed choices regarding the tradeoff
between safety and performance.
Download: thesis.pdf