CMMI, Software Testing Interview Questions | Placement Papers - Technical & HR Questions - Interview Preparation PDF Download

1. What is CMMI and what's the advantage of implementing it in an organization?

CMMI stands for Capability Maturity Model Integration. It is a process improvement approach that provides companies with the essential elements of an effective process. CMMI can serve as a good guide for process improvement across a project, organization, or division.
CMMI was formed by using multiple previous CMM processes. 

The following are the areas which CMMI addresses:

1. Systems engineering: This covers development of total systems. System engineers concentrate on converting customer needs to product solutions and supports them throughout the product lifecycle.
   
   Software engineering: Software engineers concentrate on the application of systematic, disciplined, and quantifiable approaches to the development, operation, and maintenance of software.
   
   Integrated Product and Process Development (IPPD): Integrated Product and Process Development (IPPD) is a systematic approach that achieves a timely collaboration of relevant stakeholders throughout the life of the product to better satisfy customer needs, expectations, and requirements. This section mostly concentrates on the integration part of the project for different processes. For instance, it's possible that your project is using services of some other third party component. In such situations the integration is a big task itself, and if approached in a systematic manner, can be handled with ease.
   
   Software acquisition: Many times an organization has to acquire products from other organizations. Acquisition is itself a big step for any organization and if not handled in a proper manner means a disaster is sure to happen.

2. What's the difference between implementation and institutionalization?

Both of these concepts are important while implementing a process in any organization. Any new process implemented has to go through these two phases.

Implementation: It is just performing a task within a process area. A task is performed according to a process but actions performed to complete the process are not ingrained in the organization. That means the process involved is done according to the individual point of view. When an organization starts to implement any process it first starts at this phase, i.e., implementation, and then when this process looks good it is raised to the organization level so that it can be implemented across organizations. 

Institutionalization: Institutionalization is the output of implementing the process again and again. The difference between implementation and institutionalization is in implementation if the person who implemented the process leaves the company the process is not followed, but if the process is institutionalized then even if the person leaves the organization, the process is still followed.

3. Can you explain the different maturity levels in a staged representation?

There are five maturity levels in a staged representation as shown in the following figure.

Maturity Level 1 (Initial): In this level everything is adhoc. Development is completely chaotic with budget and schedules often exceeded. In this scenario we can never predict quality. 

Maturity Level 2 (Managed): In the managed level basic project management is in place. But the basic project management and practices are followed only in the project level.

Maturity Level 3 (Defined): To reach this level the organization should have already achieved level 2. In the previous level the good practices and process were only done at the project level. But in this level all these good practices and processes are brought to the organization level. There are set and standard practices defined at the organization level which every project should follow. Maturity Level 3 moves ahead with defining a strong, meaningful, organizational approach to developing products. An important distinction between Maturity Levels 2 and 3 is that at Level 3, processes are described in more detail and more rigorously than at Level 2 and are at an organization level.

Maturity Level 4 (Quantitatively measured): To start with, this level of organization should have already achieved Level 2 and Level 3. In this level, more statistics come into the picture. Organization controls the project by statistical and other quantitative techniques. Product quality, process performance, and service quality are understood in statistical terms and are managed throughout the life of the processes. Maturity Level 4 concentrates on using metrics to make decisions and to truly measure whether progress is happening and the product is becoming better. The main difference between Levels 3 and 4 are that at Level 3, processes are qualitatively predictable. At Level 4, processes are quantitatively predictable. Level 4 addresses causes of process variation and takes corrective action.

Maturity Level 5 (Optimized): The organization has achieved goals of maturity levels 2, 3, and 4. In this level, processes are continually improved based on an understanding of common causes of variation within the processes. This is like the final level; everyone on the team is a productive member, defects are minimized, and products are delivered on time and within the budget boundary.

The following figure shows, in detail, all the maturity levels in a pictorial fashion.

4. What are the different models in CMMI?

There are two models in CMMI. The first is "staged" in which the maturity level organizes the process areas. 

The second is "continuous" in which the capability level organizes the process area.

5. How is appraisal done in CMMI?

SCAMPI stands for Standard CMMI Appraisal Method for Process Improvement. SCAMPI is an assessment process used to get CMMI certified for an organization. 

There are three classes of CMMI appraisal methods: Class A, Class B, and Class C. Class A is the most aggressive, while Class B is less aggressive, and Class C is the least aggressive.

1. et's discuss these appraisal methods in more detail.
   
   Class A: This is the only method that can provide a rating and get you a CMMI certificate. It requires all three sources of data instruments, interviews, and documents.
   
   Class B: This class requires only two sources of data (interviews and either documents or instruments). But please note you do not get rated with Class B appraisals. Class B is just a warm-up to see if an organization is ready for Class A. With less verification the appraisal takes less time. In this class data sufficiency and draft presentations are optional.
   
   Class C: This class requires only one source of data (interviews, instruments, or documents). Team consensus, validation, observation, data sufficiency, and draft presentation are optional.

6. Which appraisal method class is best?

Normally, organizations use a mix of the classes to achieve process improvement. The following are some of the strategies which an organization uses:

First Strategy: Use Class B to initiate a process improvement plan, after that apply Class C to check readiness for Class B or Class A. The following diagram shows this strategy.

Second Strategy: Class C appraisal is used on a subset of an organization. From this we get an aggregation of weakness across the organization. From this we can prepare a process improvement plan. We can then apply a Class B appraisal to see if we are ready for Class A appraisal. The following diagram shows the strategy.

Third Strategy: Class A is used to initiate an organization level process. The process improvement plan is based on an identified weakness. Class B appraisal should be performed after six months to see the readiness for the second Class A appraisal rating. The following diagram shows this strategy.

7. What different sources are needed to verify authenticity for CMMI implementation?

There are three different sources from which an appraiser can verify that an organization followed the process or not. 

Instruments: An instrument is a survey or questionnaire provided to the organization, project, or individuals before starting the assessment so that beforehand the appraiser knows some basic details of the project.

Interview: An interview is a formal meeting between one or more members of the organization in which they are asked some questions and the appraiser makes some judgments based on those interviews. During the interview the member represents some process area or role which he performs. For instance, the appraiser may interview a tester or programmer asking him indirectly what metrics he has submitted to his project manager. By this the appraiser gets a fair idea of CMMI implementation in that organization.

Documents: A document is a written work or product which serves as evidence that a process is followed. It can be hard copy, Word document, email, or any type of written official proof.

The following figure is the pictorial view of the sources used to verify how compliant the organization is with CMMI.

8. Which model should we use and under what scenarios?

Staging defines an organization process implementation sequence. So staging is a sequence of targeted process areas that describe a path of process improvement the organization will take. For instance, you cannot do your project planning (Level 2) if you have not done requirements management (Level 2). While in the continuous model you select certain process areas even if they're linked with other process areas and mature there.

So when your organization should only concentrate on specific process areas you will likely go for the continuous model. But if you want your organization to have a specific plan and to achieve not only the specific process but also any interlinked process within that process area you should go for the continuous model.

9. Can you explain capability levels in a continuous representation?

The continuous model is the same as the staged model only that the arrangement is a bit different. The continuous representation/model concentrates on the action or task to be completed within a process area. It focuses on maturing the organizations ability to perform, control, and improve the performance in that specific performance area.

Capability Level 0 Incomplete: This level means that any generic or specific practice of capability level 1 is not performed.

Capability Level 1: Performed: The capability level 1 process is expected to perform all capability level 1 specific and generic practices for that process area. In this level performance may not be stable and probably does not meet objectives such as quality, cost, and schedule, but still the task can be done.

Capability Level 2: Managed: Capability level 2 is a managed process planned properly, performed, monitored, and controlled to achieve a given purpose. Because the process is managed we achieve other objectives, such as cost, schedule, and quality. Because you are managing, certain metrics are consistently collected and applied to your management approach.

Capability Level 3: Defined: The defined process is a managed process that is tailored from an organization standard. Tailoring is done by justification and documentation guidelines. For instance your organization may have a standard that we should get an invoice from every supplier. But if the supplier is not able to supply the invoice then he should sign an agreement in place of the invoice. So here the invoice standard is not followed but the deviation is under control.

Capability Level 4: Quantitatively Managed: The quantitatively managed process is a defined process which is controlled through statistical and quantitative information. So from defect tracking to project schedules all are statistically tracked and measured for that process.

Capability Level 5: Optimizing: The optimizing process is a quantitatively managed process where we increase process performance through incremental and innovative improvements. 

Continuous representation is the same as staged only that information is arranged in a different fashion. The biggest difference is one concentrates on a specific process while the other brings a group of processes to a certain maturity level.