Software Engineering

FIGURE 9.2
Requirement decomposition and allocation flow.

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9.3 
Requirement decomposition and allocation
Requirements are decomposed to identify lower-level functional and performance 
requirements that are necessary to satisfy the original requirements. Decomposition 
provides a basis for identifying, in increasing levels of detail, how the software prod-
uct will perform its operational functions. Requirements decomposition must be per-
formed to break large, complex functions into elementary functions that can be used 
to develop structural design concepts. Requirements decomposition is necessary to 
examine the problem space addressed by a requirement and to determine the sequen-
tial or concurrent functions that must be performed to provide an adequate software 
solution to that requirement.