CMMI

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:

   
   

   

   
   

   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.

   

Software Testing Interview Questions and Answers

1. Does automation replace manual testing?
   Automation is the integration of testing tools into the test environment in such a manner that the test execution, logging, and comparison of results are done with little human intervention. A testing tool is a software application which helps automate the testing process. But the testing tool is not the complete answer for automation. One of the huge mistakes done in testing automation is automating the wrong things during development. Many testers learn the hard way that everything cannot be automated. The best components to automate are repetitive tasks. So some companies first start with manual testing and then see which tests are the most repetitive ones and only those are then automated.

   
   

   As a rule of thumb do not try to automate:

   • Unstable software: If the software is still under development and undergoing many changes automation testing will not be that effective.
   • Once in a blue moon test scripts: Do not automate test scripts which will be run once in a while.
   • Code and document review: Do not try to automate code and document reviews; they will just cause trouble.

   
   

   The following figure shows what should not be automated.

   
   

   

   
   

   All repetitive tasks which are frequently used should be automated. For instance, regression tests are prime candidates for automation because they're typically executed many times. Smoke, load, and performance tests are other examples of repetitive tasks that are suitable for automation. White box testing can also be automated using various unit testing tools. Code coverage can also be a good candidate for automation.
2. How does load testing work for websites?
   Websites have software called a web server installed on the server. The user sends a request to the web server and receives a response. So, for instance, when you type www.google.com the web server senses it and sends you the home page as a response. This happens each time you click on a link, do a submit, etc. So if we want to do load testing you need to just multiply these requests and responses "N" times. This is what an automation tool does. It first captures the request and response and then just multiplies it by "N" times and sends it to the web server, which results in load simulation.

   
   

   

   
   

   So once the tool captures the request and response, we just need to multiply the request and response with the virtual user. Virtual users are logical users which actually simulate the actual physical user by sending in the same request and response. If you want to do load testing with 10,000 users on an application it's practically impossible. But by using the load testing tool you only need to create 1000 virtual users.