Testing Maturity
Model -
Maturity levels
The
five maturity levels
The
TMM consists of 5 maturity levels that reflect a degree of test process maturity.
For each maturity level, a number of process areas are defined. A process area
is a cluster of related activities within the test process, e.g. test planning
or test training. When these activities are executed adequately, they will
contribute to an improved test process. The five levels of the TMM will support
an organisation to determine the maturity of its test process and to identify
the improvements that are necessary to achieve a higher level of test maturity.
At
level 1, testing is a chaotic, undefined process and is considered as a part of
debugging. The objective of testing at this level is to show that the software
runs without major failures. Software products are released without adequate
visibility regarding the quality and risks. In the field, the software does not
often fulfil needs, is not stable, or is too slow to work with. Within the test
project there is a lack of resources, tools and well-educated testers. There are
no process areas at this level.
At
level 2, testing is a defined process and is clearly separated from debugging.
In the context of structuring the test process, test plans are established
containing a test strategy. For deriving and selecting test cases from
requirement specifications, formal test design techniques are applied. However,
testing still starts relatively late in the development life cycle, e.g. during
the design or even during the coding phase. The main objective of testing is to
verify that the software satisfies the specified requirements.
Process
areas at level 2 are:
Detailed
guidelines for the implementation of TMM level 2: 
At
level 3, testing is fully integrated in the software life cycle. It is
identified and defined at all levels of the V-model. Test planning is done at an
early project stage by means of a master test plan. The test strategy is
determined using risk management techniques and is based on documented
requirements. A test organisation and a specific test training program exist,
and testing is perceived as being a profession. Reviews are carried out,
although not consistently and not according to a documented procedure. In
addition, to verify that the software satisfies the requirements, testing is
very much focused towards invalid testing.
Process
areas at level 3 are:
Testing
is a thoroughly defined, well-founded and measurable process. Reviews and
inspections are taking place throughout the software life cycle and are
considered to be part of testing. Software products are evaluated using quality
criteria for quality characteristics such as reliability, usability and
maintainability. Test cases are gathered, stored and managed in a central
database for re-use and regression testing. A test measurement program provides
information and visibility regarding the test process and product quality.
Testing is perceived as evaluation; it consists
of all life cycle activities concerned with checking software and
software-related work products.
Process
areas at level 4 are:
On
the basis of all results that have been achieved by fulfilling all the
improvement goals of the previous levels, testing is now a completely defined
process and one is capable of controlling the costs and the testing
effectiveness. At level 5, the methods and techniques are optimised and there is
a continuous focus on test process improvement. Amongst others “Defect
Prevention” and “Quality Control” are introduced as process areas. The
test process is characterised by sampling based quality measurements. A
procedure exists for selecting and evaluating test tools. Tools support the test
process as much as possible during test design, test execution, regression
testing, test case management, etc. Testing is a process with the objective to
prevent defects.
Process
areas at level 5 are: