Software Engineering

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CHAPTER 8 
Software Requirements Analysis Practice
should identify the actions that will be taken by the application when failures occur 
that inhibit specific types of transactions, or when the system is completely degraded.
The measures of effectiveness must be identified for the overall performance of the 
software solution (combination of the software product and computing environment) 
in achieving operational objectives. Measures of effectiveness define the desired effec-
tiveness of the solution in terms of its ability to perform its mission as expressed by 
the operational scenarios. Operational effectiveness is the overall ability of a software 
solution to achieve mission success considering the total operational environment.
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The measures of effectiveness should be specified with a minimally acceptable 
level (threshold) and desired goal (objective). This provides the range of desired 
performance against which the computational environment and application can be 
designed. 
Figure 8.2
 identifies the elements of an effectiveness measure. For an 
automobile, a measure of effectiveness can be: “The automobile should provide 
36 miles per gallon during highway driving.” This statement may seem simple, but 
there are several design factors that affect the achievement of this design goal. The 
weight, horsepower, fuel efficiency, and drag are some of the design considerations 
that would have to be managed to achieve the desired measure of effectiveness.