Topic: Software Testing Standards-CMM Levels

Software Testing Standards-CMM Levels

CMM Levels
1.Capability Maturity Model (CMM) has found it is way from Carnegie Melon University (CMU) software engineering Institute (SEI) to major Software developers all over the world. Some consider it as an answer to Software Industry�s chaotic problems, and some consider it just another exhaustive framework that requires too much to do and too little to show for it. This article is not intended to be a comprehensive introduction to CMM, the interested readers should read official CMM documentation available from SEI�s web site to get a comprehensive discussion of CMM. This article is intended to show that CMM is not a framework that advocates magical and revolutionary new ideas, but it is in fact a tailored compilation of the best practices in Software engineering.
COMPONENTS OF CMM
a)Maturity levels:A maturity level is a well-defined evolutionary plateau toward achieving a mature software process. The five maturity levels provide the top-level structure of the CMM.
b)Process capability:Software process capability describes the range of expected results that can be achieved by following a software process. The software process capability of an organization provides one means of predicting the most likely outcomes to be expected from the next software project the organization undertakes.
c)Key process area:Each maturity level is composed of key process areas. Each key process area identifies a cluster of related activities that, when performed collectively, achieve a set of goals considered important for establishing process capability at that maturity level. The key process areas have been defined to reside at a single maturity level. For example, one of the key process areas for Level 2 is Software Project Planning.
The following is the Architecture of the CMM levels



d)Goals: The goals summarize the key practices of a key process area and can be used to determine whether an organization or project has effectively implemented the key process area. The goals signify the scope, boundaries, and intent of each key process area. An example of a goal from the Software Project Planning key process area is "Software estimates are documented for use in planning and tracking the software project".
e)Common features:The key practices are divided among five Common Features sections:
1. Commitment to Perform
2. Ability to Perform
3. Activities Performed
4.Measurement and Analysis
5. Verifying Implementation.
The common features are attributes that indicate whether the implementation and institutionalization of a key process area is effective, repeatable, and lasting. The Activities Performed common feature describes implementation activities. The other four common features describe the institutionalization factors, which make a process part of the organizational culture.
f)Key practices:Each key process area is described in terms of key practices that, when implemented, help to satisfy the goals of that key process area. The key practices describe the infrastructure and activities that contribute most to the effective implementation and institutionalization of the key process area. For example, one of the practices from the Software Project Planning key process area is "The project's software development plan is developed according to a documented procedure."
CMM FRAMEWORK
MATURITY LEVELS: CMM defines five levels of maturity:
Level 1: Initial Level
This is the lowest of the maturity levels; you may consider it as the immature level. At this level the software process is not documented and is not fixed. Everything in these companies is done on an ad-hoc basis. The projects are usually late, over budgeted and have quality issues. This does not mean that a company at this level cannot do successful projects. As a matter of fact the author himself works for a company that is somewhere between Level 1 and Level 2 and despite this it has a very impressive track record for producing quality software, with in budget and with in time. Companies at Level 1 do manage to produce good software mainly because of their personnel immense competency. These companies are characterized by heroes - individuals with good programming, communications and peoples skills. It is for these individual heroes that the companies at Level 1 manage to complete successful projects. Most of the companies around the world are at Level 1. These companies make their decisions on the spur of the moment, rather than anticipating problems and fixing them before they occur. Software developers in these companies are usually over-worked, over-burdened and spend major portion of their time in re-working, or fixing bugs. The success of a project depend totally on the team working on the project and on the project manager's abilities rather than on the company's processes. As the team changes or some key individuals of the team leave - the project usually fall flat on its face.
Level 2: Repeatable Level:
At this level basic software project management practices are in place. A project planning, monitoring and measurements are properly done according to certain well-defined processes. Typical measurements include tracking of costs and schedule. The results of these measurements are used in future projects to make a better and realistic project plan. Projects have a stronger chance of being successful, and if unsuccessful the mistakes are recorded and thus are avoided in the future projects. The key point is that without measurements it is impossible to foresee and detect the problems before they get out of hand.
Level 3: Defined Level:
At this level the process of software development is fully documented. Both the managerial and technical aspects are fully defined and continued efforts are made to better the process. At this level CASE tools are used for development of software. If a Level 1company tries to follow activities involved in Level 3, the result usually are disastrous. This is because in CMM a preceding level lays the ground work for the next level. In order to be able to achieve Level 3, one must first achieve Level 2. An example of a documented process could be "the process for identifying software defects/bugs". This process may be documented by using checklist for identification of common defects; the check list may contain entries like "All variables initialized, all pointers initialized, all pointers deleted, all exceptions caught" etc. The process of defect identification may also include the total count of defects, and the categories of each software defects. A company may use any method to documents its processes. CMM lays no compulsion on how a process should be documented. The only compulsion is that the process should be documented in such a manner that a new recruit to the company can easily do his/her job by reading the documentation.
Level 4: Managed Level:
Level 3, provides a way to document the processes; Level 4 allows that documentation to be used in a meaningful manner. Level 4, involves software matrices, and statistical quality control techniques. In Level 3, I gave an example of documenting a Software Defects/bugs identification process. Imagine that the total count of defects per thousand lines of code turn out to be 500. Level 4 would have activities aimed at identifying the root cause(s) of these bugs, and would set goals to decrease the defect number to a reasonable level.
Level 5: Optimizing Level:
The software environment changes all the time. Technology changes and so do the techniques. Level 5 deals with the ongoing changes and with ways to improve the current processes to meet the changing environment. In essence Level 5 provides a positive feedback loop. Level 5 is about continuous improvement. A company at Level 5 uses statistical methods to incorporate future changes and to be receptive to ideas and technologies for continuous growth.
KEY PROCESS AREAS (KPAs):
Each level (Level 1,2, 3, 4, 5) have been divided into certain KPAs. For a company to achieve a certain maturity level it must fulfill all the KPAs of the desired maturity level. Since every company is at least at Level 1, there is no Key Process Areas for Level 1 - meaning that a Software Company does not need to do anything to be at level 1. You may think of Key Process Areas as "TO DOs of a maturity level" or a Task list that must be performed. A Key Process Area contains a group of common activities that a company must perform to fully address that Key process Area. Given below is the list of KPAs for each Maturity Level.

Level 1 - Initial
Level 2 - Repeatable
a. Requirements Management
b. Software Project Planning
c. Software Project Tracking & Oversight
d. Software Subcontract Management
e. Software Quality Assurance
f. Software Configuration Management
Level 3 - Defined
a. Organizational Process Focus
b. Organizational Process Definition
c. Training Program
d. Integrated Software Management
e. Software Product Engineering
f. Intergroup Coordination
g. Peer Reviews
Level 4 - Managed
a. Quantitative Process Management
b. Software Quality Management
Level 5 - Optimizing
a. Defect Prevention
b. Technology Change Management
c. Process Change Management

The following is the Key process Areas diagram