What is a Traceability Matrix / Requirements Traceability Matrix?

The concept of Traceability Matrix is to be able to trace from top level requirements to implementation, and from top level requirements to test.

A traceability matrix is a table that traces a requirement to the tests that are needed to verify that the requirement is fulfilled. A good traceability matrix will provide backward and forward traceability, i.e. a requirement can be traced to a test and a test to a requirements. The matrix links higher level requirements, design specifications, test requirements, and code files. It acts as a map, providing the links necessary for determining where information is located. This is also known as Requirements Traceability Matrix or RTM.

This is mostly used for QA so that they can ensure that the customer gets what they requested. The Traceability matrix also helps the developer find out why some code was implemented the way it was, by being able to go from code to Requirements. If a test fails, it is possible to use the traceability matrix to see what requirements and code the test case relates to.

The goal of a matrix of this type is -
1. To make sure that the approved requirements are addressed/covered in all phases of development: From SRS to Development to Testing to Delivery.
2. That each document should be traceable: Written test cases should be traceable to its requirement specification. If there is new version then updated testcases should be traceable with that.

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Outline for Developing a Traceability Matrix

Template for a Requirements Traceability Matrix