Information Technology Reference
In-Depth Information
• Too much design: One of the greatest problems in requirement analysis is finding
the solution to the defined problem in the same stage. A meta-requirement is a
design decision that is presented in the form of a system (product) requirement.
Meta-requirements describe situations and items that are not externally-discernible
characteristics of the system to be delivered. True meta-requirements are not
suggestions. They are items that the customer absolutely requires in the solution.
• Failure to identify properties: Sometimes, software engineers make the mis-
take of assuming that any solution to the customer's problem can only contain
items that were explicitly mentioned in the problem description and/or the
problem-space module. Some of the requirements properties could be implicit
and hidden in other requirements.
• Irrelevant information: One straightforward way to describe a solution to a
problem is to focus on what is essential, while ignoring what is inessential.
6.8 Chapter Summary and Conclusions
A requirement is a quality that a software system must have. This could be an
activity that it must perform, an interface that it must contain or an environment
within which it must operate. Requirements are criteria that a system must meet if
it to work as intended, and thus must be considered mission critical if a software
engineering project is to be successfully completed. In the last chapter, we dis-
cussed the process of eliciting these requirements from the client and from the end
user. Those requirements first elicited, however, are often times far from perfect.
In this chapter we discussed the analysis phase of the software life cycle. This
phase is focused on refining, improving and finalizing the requirements specifi-
cation, a formalized understanding of the system that will be the primary resource
for the rest of the development process. At the beginning of the analysis phase,
requirements usually suffer from one or more of the following problems:
• omitted information
• contradictory information
• ambiguous information
• inaccurate information
• irrelevant information
The analysis phase seeks to correct these problems through the systematic
evaluation, modification and refinement of a system's requirements. The system
requirements gathered during the requirements elicitation phase are then complied
into a final, functional requirements specification. During analysis, systems ana-
lysts review requirements with a goal of identifying and correcting, missing or
erroneous information. Interviews used in the requirements elicitation phase are
reviewed. When the analysts discover errors or omissions during this evaluation
period, new information is gathered to fill in the gaps by carrying out new,
