What we will discuss next is a specific black-box testing
approach. So a specific instance of the general approach that
we just saw. And this approach is the category-partition method,
and was defined by Ostrand & Balcer in 1988 in
an article to the peer [UNKNOWN] communication of the ACM.
So this is a method for going from a specification,
a description of the system, to a set of test
cases like any other black-box testing approach by following six steps.
So let's look at what these steps are. The first
step is to identify independently testable features and this is
a step that we are familiar with because its exactly
the same step that we performed in the generic black box
testing approach that we just discussed. The second step is
to identify categories. Then the next step is to partition
categories into choices. Identify constraints
among choices. Produce and evaluate
test case specifications. And finally, the sixth step is to generate
test cases from test case specifications. So two of
the key elements in these six steps are the two
that give the name to the technique so the identification
of the categories and the partition of these categories into
choices. What we're going to do next is to go
and look at each one of the steps independently, except
for the first one. Because we're already familiar with that
step, and this method doesn't really add much to it.