Review Design (by Writing Testcases)

One of the easier methods of review, for a Software Tester, is to write test conditions, test objectives, or complete testcases for the design. We define Test Conditions or Test Objectives as being statements of what is to be tested without the details usually found in testcases.

For example the following might be a few High Level Test Objectives for a design:

1. Test that the system continues to function in the event that the link to the Postal Code database is not working.
2. Test that the system switches to the backup node when the primary node is taken offline.
3. Test that the database is updated with the full CDR at the end of the call.

There is a lot of detail under these Test Objectives and potentially they could generate many, many testcases but they are all real examples and they are all necessary. They key is to look for the following while you are writing the test objectives:

1. Two, or more, test conditions that contradict each other.
2. Places where we find it difficult to write any objectives at all – this may be related to a lack of knowledge or the design may be incomplete. Either are issues.
3. Places where we are guessing at the expected behaviour for our Objective. We do not expect details here but a feeling that we don’t know what the result will be or how to prove it.

Brainstorming with other people, talking to the System Architect, looking at other similar designs and looking up technical information are all good sources for building these objectives.

Once you have completed your personnel review, you may be asked to join a group review bringing in your comments and hearing from everyone else. There are several methods of review depending on Risk including Desk Checking, Walkthroughs, Reviews, and finally Inspections. These vary from informal to very formal. However, they are all aimed at finding the errors in the design sooner rather than later. They also all assume on previous individual work.

Take a look at some of the seminars that we offer that address this situation and see if they apply to your situation. Design review is very cost-effective.

Contact us for further information.