In a software development process, a traceability matrix is a table
that correlates any two baselined documents that require a many to many
relationship to determine the completeness of the relationship. It is often used
with high-level requirements (sometimes known as marketing requirements) and
detailed requirements of the software product to the matching parts of
high-level design, detailed design, test plan, and test cases.
Common usage is to take the identifier for each of the items of one document
and place them in the left column. The identifiers for the other document are
placed across the top row. When an item in the left column is related to an item
across the top, a mark is placed in the intersecting cell. The number of
relationships are added up for each row and each column. This value indicates
the mapping of the two items. Zero values indicate that no relationship exists.
It must be determined if one must be made. Large values imply that the item is
too complex and should be simplified.
To ease with the creation of traceability matrices, it is advisable to add
the relationships to the source documents for both backward traceability and
forward traceability. In other words, when an item is changed in one baselined
document, it's easy to see what needs to be changed in the other.
