Requirements Tracing, Tracking and Reporting - Requirements Engineering and Management for Software Development Projects - page 130

9.5 When Should We Trace the Requirements?
We need to trace the requirements throughout the software development life cycle
all the time. We need to be especially careful whenever a state transition occurs in
the software development life cycle. Here are the typical stages where we need to
update the traceability matrix:
1. Whenever a change request is implemented—usually most change requests
impact requirements. So, every time we implement a change request, we need
to see if any requirement has been affected and then update the traceability
matrix with the resulting changes.
2. When we complete the software design for any module—first, we need to fill in
the references of the design document against the implemented requirements in
the traceability matrix. It is possible that some of the requirements might have
been changed to suit the design. So, we need to assess if any requirement is
impacted by the design and then update the traceability matrix.
3. Whenever a code component is completed—the coding of a component is the final
stage of implementation as testing is merely confirmation that the implementation
is defect free. It is possible that a component could have implemented multiple
requirements either fully or partially. For example, the requirement of security is
implemented across multiple components. So, as soon as we complete the coding
of a component, we need to update the traceability matrix against all the
requirements which were implemented in the component.
4. Whenever we complete unit/integration/integration testing of a component/
module/product—usually, testing does not impact a requirement. It merely
confirms that the implementation is as defect free as possible. But there are
occasions when the testing uncovers a major defect due to which we may have
to re-visit not only the code or design but also the requirements. After a test is
completed, we need to assess if such a situation has arisen due to testing and
update the traceability matrix suitably.
As we update the traceability matrix, it would become easier for us to trace any
requirement in either forward pass (passing from requirement to implementation)
or backward pass (implementation to requirement).
9.6 Tracking of Requirements
What is the big difference between tracing and tracking of requirements? Is it
different at all?
''Yep'' I would say. Tracing is just ensuring that every requirement is imple-
mented in all stages of software development. Tracing requirements through the
software development life cycle ensures that the requirement has traversed all the
stations in its path to implementation. But, what about the qualitative aspect of