Monday, 6 April 2015
Thursday, 2 April 2015
About ISTQB and Benefits for individuals
About ISTQB
The ISTQB was officially founded as an International Software Testing Qualifications Board in Edinburgh in November 2002. The international recognition of the certification is due to the participation of many countries as opposed to any country-specific scheme.
ISTQB® has created the world's most successful scheme for certifying software testers.
As of June 2013, ISTQB® has issued over 307,000 certifications in 70 countries world-wide, with a growth rate of approximately 12,000 certifications per quarter.
The main aims, tasks, and responsibilities of the ISTQB are:
To define and maintain all aspects of the ISTQB Certified Tester scheme such as core syllabi, examination structure, regulations, and certification guidelines.
To ensure that each successful participant receive the "ISTQB Certified Tester" certificate (or the local variant with the added "ISTQB compliant" logo).
To promote testing as a profession, increase the number of qualified testers, and develop a common body of understanding and knowledge about testing, through the syllabus & terminology.
To approve, monitor compliance, or expel national boards.
Read more about the ISTQB www.istqb.org
Some advantages offered by the ISTQB Certified Tester scheme are:
Testers don't need to know English in order to gain a recognized qualification with less cultural bias. It also allows them to move across country borders.
Economic benefits accrue to testing-related suppliers such as training providers, consultants, etc. in all participating countries.
European/multinational/international projects can have a common understanding of testing issues.
Benefits for individuals
ISTQB® certified testers:
Gain independently assessed knowledge and skills.
Increase their marketability throughout the industry.
Have greater career opportunities and increased earning potential.
Can add the "ISTQB® Certified Tester" logo and credential to their resumes.
Are recognized as having subscribed to a Code of Ethics.
Benefits for employers
Employers of ISTQB® Certified Testers can take advantage of many benefits, as shown below:
Having certified staff can be a competitive advantage for organizations, which can benefit from the adoption of more structured testing practices and optimization of test activities, derived from the ISTQB®competencies.
For consulting organizations, certified staff can offer high-level services to customers, increasing revenues and brand value.
Adoption of ISTQB® certification schemes in an organization can help in recruiting and retaining high standing staff and can help organizations remain up-to-date with testing innovations.
Formal recognition for organizations having adopted ISTQB® certifications will be available in the future.
Benefits for training providers
ISTQB® Training providers can:
Access an international market that recognizes ISTQB®.
Distinguish themselves through the independently assessed professionalism of their teachers and quality/ coverage of their training material.
Offer their clients the most up-to-date testing knowledge.
Provide a continuously expanding professional development path to their clients in the field of testing.
Participate in early reviews of the ISTQB® syllabi and in other activities organized by ISTQB®.
Use the ISTQB® accredited trainer provider logos and credential within their marketing materials.
The ISTQB was officially founded as an International Software Testing Qualifications Board in Edinburgh in November 2002. The international recognition of the certification is due to the participation of many countries as opposed to any country-specific scheme.
ISTQB® has created the world's most successful scheme for certifying software testers.
As of June 2013, ISTQB® has issued over 307,000 certifications in 70 countries world-wide, with a growth rate of approximately 12,000 certifications per quarter.
The main aims, tasks, and responsibilities of the ISTQB are:
To define and maintain all aspects of the ISTQB Certified Tester scheme such as core syllabi, examination structure, regulations, and certification guidelines.
To ensure that each successful participant receive the "ISTQB Certified Tester" certificate (or the local variant with the added "ISTQB compliant" logo).
To promote testing as a profession, increase the number of qualified testers, and develop a common body of understanding and knowledge about testing, through the syllabus & terminology.
To approve, monitor compliance, or expel national boards.
Read more about the ISTQB www.istqb.org
Some advantages offered by the ISTQB Certified Tester scheme are:
Testers don't need to know English in order to gain a recognized qualification with less cultural bias. It also allows them to move across country borders.
Economic benefits accrue to testing-related suppliers such as training providers, consultants, etc. in all participating countries.
European/multinational/international projects can have a common understanding of testing issues.
Benefits for individuals
ISTQB® certified testers:
Gain independently assessed knowledge and skills.
Increase their marketability throughout the industry.
Have greater career opportunities and increased earning potential.
Can add the "ISTQB® Certified Tester" logo and credential to their resumes.
Are recognized as having subscribed to a Code of Ethics.
Benefits for employers
Employers of ISTQB® Certified Testers can take advantage of many benefits, as shown below:
Having certified staff can be a competitive advantage for organizations, which can benefit from the adoption of more structured testing practices and optimization of test activities, derived from the ISTQB®competencies.
For consulting organizations, certified staff can offer high-level services to customers, increasing revenues and brand value.
Adoption of ISTQB® certification schemes in an organization can help in recruiting and retaining high standing staff and can help organizations remain up-to-date with testing innovations.
Formal recognition for organizations having adopted ISTQB® certifications will be available in the future.
Benefits for training providers
ISTQB® Training providers can:
Access an international market that recognizes ISTQB®.
Distinguish themselves through the independently assessed professionalism of their teachers and quality/ coverage of their training material.
Offer their clients the most up-to-date testing knowledge.
Provide a continuously expanding professional development path to their clients in the field of testing.
Participate in early reviews of the ISTQB® syllabi and in other activities organized by ISTQB®.
Use the ISTQB® accredited trainer provider logos and credential within their marketing materials.
Mobile application development and testing process
Recently, we have been involved in mobile application development and testing. The below checklist ensures that both developers and testers have covered these high level scenarios during their requirements discussion, development and testing activities. Mobile application development and testing checklist also helps you refine your requirements to ensure that your scope of work is clearly defined. These are high level questions and not very specific to the application functionality (we will cover that in the next article in the series).
1. Which mobile platform to develop for? iOS or Android?
iOS and Android are the preferred platform for developing mobile applications. However, Blackberry is still used by several enterprise users and a significant population of the developing world still uses Symbian phones. It’s good to know upfront which platforms are expected to be supported. This will help you make crucial decisions regarding your architecture / design and also provide inputs on whether you want to develop a completely native application or use a framework like PhoneGap. Popular platforms are listed below:
Android
iOS
Windows Mobile
Blackberry
Symbian
Mobile application development and testing smartphone market share
Mobile Application Testing Device Units Forecast
This Forbes article provides details on the current market share and forecast, based on mobile OS.
2. Which version of iOS should I target? What version of Android should I develop for?
Does your application use any features introduced in a specific version of the OS? If so, you will want to mention this in your marketing material and also test it on the target OS. It is also good practice to prevent the application from being installed on OS versions that are not supported. This will avoid users leaving low ratings and negative feedback after installing the application on an unsupported OS. Of course, you will want to test and ensure that your application works on the targeted OS version.
Mobile application developmentmobile application testing iOS Version chart
The above image shows the usage statistics for different version of the Android and iOS. Google provides updated metrics for the version of Android being used across all android devices and information on how you can support multiple versions. Apple also provides statistics for iOS version usage along with a checklist of their own (These stats are from Sept 2013 before iOS7 launched).
3. Device Hardware Requirements
Does your application have any specific hardware requirements like memory, camera, CPUs etc? As mentioned above, it’s best to prevent installation on unsupported devices programmatically when possible. Here are instructions to check if your device has sufficient memory/RAM in Android and iOS and also to check for camera on iOS and Android.
4. Which screen resolution should I target?
Make sure that your application looks good on your target screen resolution. Smartphones and tablets come in all shapes and sizes. A list of devices with screen resolution and display density is available on Wikipedia. Some of the common screen resolutions are below:
320 x 480px
640 x 960px
480 x 800px
720 x 1280px
768 x 1280px
800 x 1280px
1200 x 1920px
2048 × 1536px
Google also provides statistics on the number of devices that have a particular physical screen size and density. Information on pixel count for various screen sizes and how you can support multiple screen sizes is also available.
5. Should I develop another app for tablets?
It’s good practice to use high quality graphics for large devices like tablets especially if your application or game is expected to be used on these devices. Some developers release a separate HD version of the application/game instead of using a single package. Irrespective of your implementation process, it’s good practice to test on both devices if you expect significant users on both. Google has also released an app quality checklist to help developers deliver quality apps for tablet devices.
6. Portrait or Landscape Orientation?
Some games work only in landscape mode while some applications are designed to work in portrait mode only and other work in both modes. Make sure you test your applications to see if there are any issues when changing the orientation like application crashing or UI bugs.
7. Testing GPS functionality, Accelerometer, Hardware keys
If your application requires use of the following hardware features, your test cases also need to test for scenarios when they are not available -
Hardware keys – Ex. Camera application using a dedicated camera button, Task/Event Manager applications using hardware buttons to snooze a reminder, media players using volume and other keys etc. Some applications also use the power button to provide additional functionality / shortcuts to application behavior.
Accelerometer – Applications that make use of accelerometer require testing to ensure that the readings are being recorded accurately and utilized correctly within the applications. This test case might be relevant to applications like Star Maps, Pedometers, Jump trackers, Games, 3D visualization applications etc
GPS – How will your Navigation applications respond if the GPS is disabled or turned off abruptly during operation?
Any other sensor – If you application depends on additional sensors for temperature, luminosity or any accessory that provides additional functionality, then you need to ensure that you have tested for conditions when they are not available or do not function accurately.
8. Network Connectivity Issues – GPRS, 2G, 3G, WiFi, Intermittent connectivity, No connectivity
Most of the applications are developed in the presence of WiFi which provides good network connectivity. However it’s important to test applications in the real world where the user might not have access to WiFi. Usually when people are on the move, network connectivity is intermittent with connection being dropped once in a while. Network speeds also vary based on the users location and the kind of connectivity they are paying for. Applications must be able to handle these situations gracefully and they must be tested for it.
9. Test Mobile + web app updates
Does your mobile application have a server side component or a web service it uses? Does the mobile application need an update when the server side component is updated? If so, make sure there is a test case to track this to avoid any human error.
10. Testing interruptions to the mobile app
There are various events that can interrupt the flow of your application. Your application should be able to handle these and should be tested for the same.
Incoming Call
Text message
Other app notifications
Storage low
Battery low
Battery dead
No storage
Airplane mode
Intermittent connectivity
Home screen jump
Sleep mode
11. Mobile application security testing
Security and data privacy are of utmost importance in today’s scenario. Users are worried about their data and credentials being exposed through vulnerable applications.
Is your application storing payment information or credit card details?
Does your application use secure network protocols?
Can they be switched to insecure ones?
Does the application ask for more permissions than it needs?
Does your application use certificates?
Does your application use a Device ID as an identifier?
Does your application require a user to be authenticated before they are allowed to access their data?
Is there a maximum number of login attempts before they are locked out?
Applications should encrypt user name and passwords when authenticating the user over a network. One way to test security related scenarios is to route your mobile’s data through a proxy server like OWASP Zed Attack Proxy and look for vulnerabilities.
12. Testing In-app payment, advertisements and payment gateway integrations
If your app makes use of in-app payment, advertisements or payment gateways for e-commerce transactions, you will need to test the functionality end to end to ensure that there are no issues in the transactions. Testing for payment gateway integration and advertisements will need accounts to be created with the Payment Gateways and Advertisement servers before testing can begin.
13. Mobile application performance testing
Have you checked to see if the performance of your mobile application degrades with increase in the – size of mailbox, album, messages, music or any other content relevant to the application?
It’s good practice to test your application for performance and scalability issues. With large storage capacity being available at affordable prices, it’s not uncommon for users to have large amount of data / content on their smartphone. Users even store SMS for several years on their smartphones. If your application has user generated content / data associated with it (Ex. Photographs, SMS etc) which can grow to huge proportions over the lifetime of the application, your testing should include these scenarios to see how the application performs. In case the application has a server side component, you should also test the application with increasing number of users. While this testing can be done manually, we have tools like Little Eye and Neo Load that can help you with Performance and Load testing of your mobile application.
14. Mobile Application Localization and Timezone issues
If your application is multilingual, it needs to be tested in other languages to ensure that there is no character encoding issue, data truncation issue or any UI issues due to varying character lengths. You also need to test applications to ensure that they handle timezone changes. What happens if a user travels forward across timezone and returns to his/her previous timezone? How does your app handle entries with date and time which are in sequence but not in chronological order?
15. Testing Social network integration
Many applications these days ship with the ability to share a post from the application, on the users’ social networking account. However most users would like to be prompted before a post is published on their account. Does your application handle this? Are they being allowed to share the status message being shared?
16. Test hardware connectivity – Bluetooth, WiFi, NFC, USB – Device recognition
Smartphones come with a plethora of connectivity options. If your application makes use of the below connectivity options (Ex. File managers or photo editors that let you share your file, AirDroid which allows you to transfer files between PC and your mobile over wifi) then you should test them to ensure they work as expected. You should also test to see how they handle errors when the connection is lost during a transfer / transaction. Commonly used mechanism to share data or transact are:
Bluetooth
WiFi
USB
NFC
17. Google Play / Apple App store integration and supported device list/restrictions
Consultants and organizations that provide end to end services should also include test cases to ensure that the mobile app is successfully deployed to the App store / Play store and is only available to the supported devices. This could also include validation of all the text, screenshots, version numbers etc that are part of the app listing.
In the next article in this series we will cover test cases related to mobile application functionality.
If you found this post useful, please share it with your friends / colleagues.
1. Which mobile platform to develop for? iOS or Android?
iOS and Android are the preferred platform for developing mobile applications. However, Blackberry is still used by several enterprise users and a significant population of the developing world still uses Symbian phones. It’s good to know upfront which platforms are expected to be supported. This will help you make crucial decisions regarding your architecture / design and also provide inputs on whether you want to develop a completely native application or use a framework like PhoneGap. Popular platforms are listed below:
Android
iOS
Windows Mobile
Blackberry
Symbian
Mobile application development and testing smartphone market share
Mobile Application Testing Device Units Forecast
This Forbes article provides details on the current market share and forecast, based on mobile OS.
2. Which version of iOS should I target? What version of Android should I develop for?
Does your application use any features introduced in a specific version of the OS? If so, you will want to mention this in your marketing material and also test it on the target OS. It is also good practice to prevent the application from being installed on OS versions that are not supported. This will avoid users leaving low ratings and negative feedback after installing the application on an unsupported OS. Of course, you will want to test and ensure that your application works on the targeted OS version.
Mobile application developmentmobile application testing iOS Version chart
The above image shows the usage statistics for different version of the Android and iOS. Google provides updated metrics for the version of Android being used across all android devices and information on how you can support multiple versions. Apple also provides statistics for iOS version usage along with a checklist of their own (These stats are from Sept 2013 before iOS7 launched).
3. Device Hardware Requirements
Does your application have any specific hardware requirements like memory, camera, CPUs etc? As mentioned above, it’s best to prevent installation on unsupported devices programmatically when possible. Here are instructions to check if your device has sufficient memory/RAM in Android and iOS and also to check for camera on iOS and Android.
4. Which screen resolution should I target?
Make sure that your application looks good on your target screen resolution. Smartphones and tablets come in all shapes and sizes. A list of devices with screen resolution and display density is available on Wikipedia. Some of the common screen resolutions are below:
320 x 480px
640 x 960px
480 x 800px
720 x 1280px
768 x 1280px
800 x 1280px
1200 x 1920px
2048 × 1536px
Google also provides statistics on the number of devices that have a particular physical screen size and density. Information on pixel count for various screen sizes and how you can support multiple screen sizes is also available.
5. Should I develop another app for tablets?
It’s good practice to use high quality graphics for large devices like tablets especially if your application or game is expected to be used on these devices. Some developers release a separate HD version of the application/game instead of using a single package. Irrespective of your implementation process, it’s good practice to test on both devices if you expect significant users on both. Google has also released an app quality checklist to help developers deliver quality apps for tablet devices.
6. Portrait or Landscape Orientation?
Some games work only in landscape mode while some applications are designed to work in portrait mode only and other work in both modes. Make sure you test your applications to see if there are any issues when changing the orientation like application crashing or UI bugs.
7. Testing GPS functionality, Accelerometer, Hardware keys
If your application requires use of the following hardware features, your test cases also need to test for scenarios when they are not available -
Hardware keys – Ex. Camera application using a dedicated camera button, Task/Event Manager applications using hardware buttons to snooze a reminder, media players using volume and other keys etc. Some applications also use the power button to provide additional functionality / shortcuts to application behavior.
Accelerometer – Applications that make use of accelerometer require testing to ensure that the readings are being recorded accurately and utilized correctly within the applications. This test case might be relevant to applications like Star Maps, Pedometers, Jump trackers, Games, 3D visualization applications etc
GPS – How will your Navigation applications respond if the GPS is disabled or turned off abruptly during operation?
Any other sensor – If you application depends on additional sensors for temperature, luminosity or any accessory that provides additional functionality, then you need to ensure that you have tested for conditions when they are not available or do not function accurately.
8. Network Connectivity Issues – GPRS, 2G, 3G, WiFi, Intermittent connectivity, No connectivity
Most of the applications are developed in the presence of WiFi which provides good network connectivity. However it’s important to test applications in the real world where the user might not have access to WiFi. Usually when people are on the move, network connectivity is intermittent with connection being dropped once in a while. Network speeds also vary based on the users location and the kind of connectivity they are paying for. Applications must be able to handle these situations gracefully and they must be tested for it.
9. Test Mobile + web app updates
Does your mobile application have a server side component or a web service it uses? Does the mobile application need an update when the server side component is updated? If so, make sure there is a test case to track this to avoid any human error.
10. Testing interruptions to the mobile app
There are various events that can interrupt the flow of your application. Your application should be able to handle these and should be tested for the same.
Incoming Call
Text message
Other app notifications
Storage low
Battery low
Battery dead
No storage
Airplane mode
Intermittent connectivity
Home screen jump
Sleep mode
11. Mobile application security testing
Security and data privacy are of utmost importance in today’s scenario. Users are worried about their data and credentials being exposed through vulnerable applications.
Is your application storing payment information or credit card details?
Does your application use secure network protocols?
Can they be switched to insecure ones?
Does the application ask for more permissions than it needs?
Does your application use certificates?
Does your application use a Device ID as an identifier?
Does your application require a user to be authenticated before they are allowed to access their data?
Is there a maximum number of login attempts before they are locked out?
Applications should encrypt user name and passwords when authenticating the user over a network. One way to test security related scenarios is to route your mobile’s data through a proxy server like OWASP Zed Attack Proxy and look for vulnerabilities.
12. Testing In-app payment, advertisements and payment gateway integrations
If your app makes use of in-app payment, advertisements or payment gateways for e-commerce transactions, you will need to test the functionality end to end to ensure that there are no issues in the transactions. Testing for payment gateway integration and advertisements will need accounts to be created with the Payment Gateways and Advertisement servers before testing can begin.
13. Mobile application performance testing
Have you checked to see if the performance of your mobile application degrades with increase in the – size of mailbox, album, messages, music or any other content relevant to the application?
It’s good practice to test your application for performance and scalability issues. With large storage capacity being available at affordable prices, it’s not uncommon for users to have large amount of data / content on their smartphone. Users even store SMS for several years on their smartphones. If your application has user generated content / data associated with it (Ex. Photographs, SMS etc) which can grow to huge proportions over the lifetime of the application, your testing should include these scenarios to see how the application performs. In case the application has a server side component, you should also test the application with increasing number of users. While this testing can be done manually, we have tools like Little Eye and Neo Load that can help you with Performance and Load testing of your mobile application.
14. Mobile Application Localization and Timezone issues
If your application is multilingual, it needs to be tested in other languages to ensure that there is no character encoding issue, data truncation issue or any UI issues due to varying character lengths. You also need to test applications to ensure that they handle timezone changes. What happens if a user travels forward across timezone and returns to his/her previous timezone? How does your app handle entries with date and time which are in sequence but not in chronological order?
15. Testing Social network integration
Many applications these days ship with the ability to share a post from the application, on the users’ social networking account. However most users would like to be prompted before a post is published on their account. Does your application handle this? Are they being allowed to share the status message being shared?
16. Test hardware connectivity – Bluetooth, WiFi, NFC, USB – Device recognition
Smartphones come with a plethora of connectivity options. If your application makes use of the below connectivity options (Ex. File managers or photo editors that let you share your file, AirDroid which allows you to transfer files between PC and your mobile over wifi) then you should test them to ensure they work as expected. You should also test to see how they handle errors when the connection is lost during a transfer / transaction. Commonly used mechanism to share data or transact are:
Bluetooth
WiFi
USB
NFC
17. Google Play / Apple App store integration and supported device list/restrictions
Consultants and organizations that provide end to end services should also include test cases to ensure that the mobile app is successfully deployed to the App store / Play store and is only available to the supported devices. This could also include validation of all the text, screenshots, version numbers etc that are part of the app listing.
In the next article in this series we will cover test cases related to mobile application functionality.
If you found this post useful, please share it with your friends / colleagues.
What is Prototype model- advantages, disadvantages and when to use it?
The basic idea here is that instead of freezing the requirements before a design or coding can proceed, a throwaway prototype is built to understand the requirements. This prototype is developed based on the currently known requirements. By using this prototype, the client can get an “actual feel” of the system, since the interactions with prototype can enable the client to better understand the requirements of the desired system. Prototyping is an attractive idea for complicated and large systems for which there is no manual process or existing system to help determining the requirements. The prototype are usually not complete systems and many of the details are not built in the prototype. The goal is to provide a system with overall functionality.
Diagram of Prototype model:
Prototype model
Advantages of Prototype model:
Users are actively involved in the development
Since in this methodology a working model of the system is provided, the users get a better understanding of the system being developed.
Errors can be detected much earlier.
Quicker user feedback is available leading to better solutions.
Missing functionality can be identified easily
Confusing or difficult functions can be identified
Requirements validation, Quick implementation of, incomplete, but
functional, application.
Disadvantages of Prototype model:
Leads to implementing and then repairing way of building systems.
Practically, this methodology may increase the complexity of the system as scope of the system may expand beyond original plans.
Incomplete application may cause application not to be used as the
full system was designed
Incomplete or inadequate problem analysis.
When to use Prototype model:
Prototype model should be used when the desired system needs to have a lot of interaction with the end users.
Typically, online systems, web interfaces have a very high amount of interaction with end users, are best suited for Prototype model. It might take a while for a system to be built that allows ease of use and needs minimal training for the end user.
Prototyping ensures that the end users constantly work with the system and provide a feedback which is incorporated in the prototype to result in a useable system. They are excellent for designing good human computer interface systems.
Diagram of Prototype model:
Prototype model
Advantages of Prototype model:
Users are actively involved in the development
Since in this methodology a working model of the system is provided, the users get a better understanding of the system being developed.
Errors can be detected much earlier.
Quicker user feedback is available leading to better solutions.
Missing functionality can be identified easily
Confusing or difficult functions can be identified
Requirements validation, Quick implementation of, incomplete, but
functional, application.
Disadvantages of Prototype model:
Leads to implementing and then repairing way of building systems.
Practically, this methodology may increase the complexity of the system as scope of the system may expand beyond original plans.
Incomplete application may cause application not to be used as the
full system was designed
Incomplete or inadequate problem analysis.
When to use Prototype model:
Prototype model should be used when the desired system needs to have a lot of interaction with the end users.
Typically, online systems, web interfaces have a very high amount of interaction with end users, are best suited for Prototype model. It might take a while for a system to be built that allows ease of use and needs minimal training for the end user.
Prototyping ensures that the end users constantly work with the system and provide a feedback which is incorporated in the prototype to result in a useable system. They are excellent for designing good human computer interface systems.
Spiral model- advantages, disadvantages and when to use it?
The spiral model is similar to the incremental model, with more emphasis placed on risk analysis. The spiral model has four phases: Planning, Risk Analysis, Engineering and Evaluation. A software project repeatedly passes through these phases in iterations (called Spirals in this model). The baseline spiral, starting in the planning phase, requirements are gathered and risk is assessed. Each subsequent spirals builds on the baseline spiral.
Planning Phase: Requirements are gathered during the planning phase. Requirements like ‘BRS’ that is ‘Bussiness Requirement Specifications’ and ‘SRS’ that is ‘System Requirement specifications’.
Risk Analysis: In the risk analysis phase, a process is undertaken to identify risk and alternate solutions. A prototype is produced at the end of the risk analysis phase. If any risk is found during the risk analysis then alternate solutions are suggested and implemented.
Engineering Phase: In this phase software is developed, along with testing at the end of the phase. Hence in this phase the development and testing is done.
Evaluation phase: This phase allows the customer to evaluate the output of the project to date before the project continues to the next spiral.
Diagram of Spiral model:
Spiral model
Advantages of Spiral model:
High amount of risk analysis hence, avoidance of Risk is enhanced.
Good for large and mission-critical projects.
Strong approval and documentation control.
Additional Functionality can be added at a later date.
Software is produced early in the software life cycle.
Disadvantages of Spiral model:
Can be a costly model to use.
Risk analysis requires highly specific expertise.
Project’s success is highly dependent on the risk analysis phase.
Doesn’t work well for smaller projects.
When to use Spiral model:
When costs and risk evaluation is important
For medium to high-risk projects
Long-term project commitment unwise because of potential changes to economic priorities
Users are unsure of their needs
Requirements are complex
New product line
Significant changes are expected (research and exploration)
Planning Phase: Requirements are gathered during the planning phase. Requirements like ‘BRS’ that is ‘Bussiness Requirement Specifications’ and ‘SRS’ that is ‘System Requirement specifications’.
Risk Analysis: In the risk analysis phase, a process is undertaken to identify risk and alternate solutions. A prototype is produced at the end of the risk analysis phase. If any risk is found during the risk analysis then alternate solutions are suggested and implemented.
Engineering Phase: In this phase software is developed, along with testing at the end of the phase. Hence in this phase the development and testing is done.
Evaluation phase: This phase allows the customer to evaluate the output of the project to date before the project continues to the next spiral.
Diagram of Spiral model:
Spiral model
Advantages of Spiral model:
High amount of risk analysis hence, avoidance of Risk is enhanced.
Good for large and mission-critical projects.
Strong approval and documentation control.
Additional Functionality can be added at a later date.
Software is produced early in the software life cycle.
Disadvantages of Spiral model:
Can be a costly model to use.
Risk analysis requires highly specific expertise.
Project’s success is highly dependent on the risk analysis phase.
Doesn’t work well for smaller projects.
When to use Spiral model:
When costs and risk evaluation is important
For medium to high-risk projects
Long-term project commitment unwise because of potential changes to economic priorities
Users are unsure of their needs
Requirements are complex
New product line
Significant changes are expected (research and exploration)
Agile model – advantages, disadvantages and when to use it?
Agile development model is also a type of Incremental model. Software is developed in incremental, rapid cycles. This results in small incremental releases with each release building on previous functionality. Each release is thoroughly tested to ensure software quality is maintained. It is used for time critical applications. Extreme Programming (XP) is currently one of the most well known agile development life cycle model.
Diagram of Agile model:
Agile model in Software testing
Advantages of Agile model:
Customer satisfaction by rapid, continuous delivery of useful software.
People and interactions are emphasized rather than process and tools. Customers, developers and testers constantly interact with each other.
Working software is delivered frequently (weeks rather than months).
Face-to-face conversation is the best form of communication.
Close, daily cooperation between business people and developers.
Continuous attention to technical excellence and good design.
Regular adaptation to changing circumstances.
Even late changes in requirements are welcomed
Disadvantages of Agile model:
In case of some software deliverables, especially the large ones, it is difficult to assess the effort required at the beginning of the software development life cycle.
There is lack of emphasis on necessary designing and documentation.
The project can easily get taken off track if the customer representative is not clear what final outcome that they want.
Only senior programmers are capable of taking the kind of decisions required during the development process. Hence it has no place for newbie programmers, unless combined with experienced resources.
When to use Agile model:
When new changes are needed to be implemented. The freedom agile gives to change is very important. New changes can be implemented at very little cost because of the frequency of new increments that are produced.
To implement a new feature the developers need to lose only the work of a few days, or even only hours, to roll back and implement it.
Unlike the waterfall model in agile model very limited planning is required to get started with the project. Agile assumes that the end users’ needs are ever changing in a dynamic business and IT world. Changes can be discussed and features can be newly effected or removed based on feedback. This effectively gives the customer the finished system they want or need.
Both system developers and stakeholders alike, find they also get more freedom of time and options than if the software was developed in a more rigid sequential way. Having options gives them the ability to leave important decisions until more or better data or even entire hosting programs are available; meaning the project can continue to move forward without fear of reaching a sudden standstill.
Diagram of Agile model:
Agile model in Software testing
Advantages of Agile model:
Customer satisfaction by rapid, continuous delivery of useful software.
People and interactions are emphasized rather than process and tools. Customers, developers and testers constantly interact with each other.
Working software is delivered frequently (weeks rather than months).
Face-to-face conversation is the best form of communication.
Close, daily cooperation between business people and developers.
Continuous attention to technical excellence and good design.
Regular adaptation to changing circumstances.
Even late changes in requirements are welcomed
Disadvantages of Agile model:
In case of some software deliverables, especially the large ones, it is difficult to assess the effort required at the beginning of the software development life cycle.
There is lack of emphasis on necessary designing and documentation.
The project can easily get taken off track if the customer representative is not clear what final outcome that they want.
Only senior programmers are capable of taking the kind of decisions required during the development process. Hence it has no place for newbie programmers, unless combined with experienced resources.
When to use Agile model:
When new changes are needed to be implemented. The freedom agile gives to change is very important. New changes can be implemented at very little cost because of the frequency of new increments that are produced.
To implement a new feature the developers need to lose only the work of a few days, or even only hours, to roll back and implement it.
Unlike the waterfall model in agile model very limited planning is required to get started with the project. Agile assumes that the end users’ needs are ever changing in a dynamic business and IT world. Changes can be discussed and features can be newly effected or removed based on feedback. This effectively gives the customer the finished system they want or need.
Both system developers and stakeholders alike, find they also get more freedom of time and options than if the software was developed in a more rigid sequential way. Having options gives them the ability to leave important decisions until more or better data or even entire hosting programs are available; meaning the project can continue to move forward without fear of reaching a sudden standstill.
What is Capability Maturity Model (CMM)? What are CMM Levels?
Capability Maturity Model is a bench-mark for measuring the maturity of an organization’s software process. It is a methodology used to develop and refine an organization’s software development process. CMM can be used to assess an organization against a scale of five process maturity levels based on certain Key Process Areas (KPA). It describes the maturity of the company based upon the project the company is dealing with and the clients. Each level ranks the organization according to its standardization of processes in the subject area being assessed.
A maturity model provides:
A place to start
The benefit of a community’s prior experiences
A common language and a shared vision
A framework for prioritizing actions
A way to define what improvement means for your organization
In CMMI models with a staged representation, there are five maturity levels designated by the numbers 1 through 5 as shown below:
Initial
Managed
Defined
Quantitatively Managed
Optimizing
CMM level diagram - Characteristics of maturity levelsMaturity levels consist of a predefined set of process areas. The maturity levels are measured by the achievement of the specific and generic goals that apply to each predefined set of process areas. The following sections describe the characteristics of each maturity level in detail.
Maturity Level 1 – Initial: Company has no standard process for software development. Nor does it have a project-tracking system that enables developers to predict costs or finish dates with any accuracy.
In detail we can describe it as given below:
At maturity level 1, processes are usually ad hoc and chaotic.
The organization usually does not provide a stable environment. Success in these organizations depends on the competence and heroics of the people in the organization and not on the use of proven processes.
Maturity level 1 organizations often produce products and services that work but company has no standard process for software development. Nor does it have a project-tracking system that enables developers to predict costs or finish dates with any accuracy.
Maturity level 1 organizations are characterized by a tendency to over commit, abandon processes in the time of crisis, and not be able to repeat their past successes.
Maturity Level 2 – Managed: Company has installed basic software management processes and controls. But there is no consistency or coordination among different groups.
In detail we can describe it as given below:
At maturity level 2, an organization has achieved all the specific and generic goals of the maturity level 2 process areas. In other words, the projects of the organization have ensured that requirements are managed and that processes are planned, performed, measured, and controlled.
The process discipline reflected by maturity level 2 helps to ensure that existing practices are retained during times of stress. When these practices are in place, projects are performed and managed according to their documented plans.
At maturity level 2, requirements, processes, work products, and services are managed. The status of the work products and the delivery of services are visible to management at defined points.
Commitments are established among relevant stakeholders and are revised as needed. Work products are reviewed with stakeholders and are controlled.
The work products and services satisfy their specified requirements, standards, and objectives.
Maturity Level 3 – Defined: Company has pulled together a standard set of processes and controls for the entire organization so that developers can move between projects more easily and customers can begin to get consistency from different groups.
In detail we can describe it as given below:
At maturity level 3, an organization has achieved all the specific and generic goals.
At maturity level 3, processes are well characterized and understood, and are described in standards, procedures, tools, and methods.
A critical distinction between maturity level 2 and maturity level 3 is the scope of standards, process descriptions, and procedures. At maturity level 2, the standards, process descriptions, and procedures may be quite different in each specific instance of the process (for example, on a particular project). At maturity level 3, the standards, process descriptions, and procedures for a project are tailored from the organization’s set of standard processes to suit a particular project or organizational unit.
The organization’s set of standard processes includes the processes addressed at maturity level 2 and maturity level 3. As a result, the processes that are performed across the organization are consistent except for the differences allowed by the tailoring guidelines.
Another critical distinction is that at maturity level 3, processes are typically described in more detail and more rigorously than at maturity level 2.
At maturity level 3, processes are managed more proactively using an understanding of the interrelationships of the process activities and detailed measures of the process, its work products, and its services.
Maturity Level 4 – Quantitatively Managed: In addition to implementing standard processes, company has installed systems to measure the quality of those processes across all projects.
In detail we can describe it as given below:
At maturity level 4, an organization has achieved all the specific goals of the process areas assigned to maturity levels 2, 3, and 4 and the generic goals assigned to maturity levels 2 and 3.
At maturity level 4 Sub-processes are selected that significantly contribute to overall process performance. These selected sub-processes are controlled using statistical and other quantitative techniques.
Quantitative objectives for quality and process performance are established and used as criteria in managing processes. Quantitative objectives are based on the needs of the customer, end users, organization, and process implementers. Quality and process performance are understood in statistical terms and are managed throughout the life of the processes.
For these processes, detailed measures of process performance are collected and statistically analyzed. Special causes of process variation are identified and, where appropriate, the sources of special causes are corrected to prevent future occurrences.
Quality and process performance measures are incorporated into the organizations measurement repository to support fact-based decision making in the future.
A critical distinction between maturity level 3 and maturity level 4 is the predictability of process performance. At maturity level 4, the performance of processes is controlled using statistical and other quantitative techniques, and is quantitatively predictable. At maturity level 3, processes are only qualitatively predictable.
Maturity Level 5 – Optimizing: Company has accomplished all of the above and can now begin to see patterns in performance over time, so it can tweak its processes in order to improve productivity and reduce defects in software development across the entire organization.
In detail we can describe it as given below:
At maturity level 5, an organization has achieved all the specific goals of the process areas assigned to maturity levels 2, 3, 4, and 5 and the generic goals assigned to maturity levels 2 and 3.
Processes are continually improved based on a quantitative understanding of the common causes of variation inherent in processes.
Maturity level 5 focuses on continually improving process performance through both incremental and innovative technological improvements.
Quantitative process-improvement objectives for the organization are established, continually revised to reflect changing business objectives, and used as criteria in managing process improvement.
The effects of deployed process improvements are measured and evaluated against the quantitative process-improvement objectives. Both the defined processes and the organization’s set of standard processes are targets of measurable improvement activities.
Optimizing processes that are agile and innovative depends on the participation of an empowered workforce aligned with the business values and objectives of the organization.
The organization’s ability to rapidly respond to changes and opportunities is enhanced by finding ways to accelerate and share learning. Improvement of the processes is inherently part of everybody’s role, resulting in a cycle of continual improvement.
A critical distinction between maturity level 4 and maturity level 5 is the type of process variation addressed. At maturity level 4, processes are concerned with addressing special causes of process variation and providing statistical predictability of the results. Though processes may produce predictable results, the results may be insufficient to achieve the established objectives. At maturity level 5, processes are concerned with addressing common causes of process variation and changing the process (that is, shifting the mean of the process performance) to improve process performance (while maintaining statistical predictability) to achieve the established quantitative process-improvement objectives.
A maturity model provides:
A place to start
The benefit of a community’s prior experiences
A common language and a shared vision
A framework for prioritizing actions
A way to define what improvement means for your organization
In CMMI models with a staged representation, there are five maturity levels designated by the numbers 1 through 5 as shown below:
Initial
Managed
Defined
Quantitatively Managed
Optimizing
CMM level diagram - Characteristics of maturity levelsMaturity levels consist of a predefined set of process areas. The maturity levels are measured by the achievement of the specific and generic goals that apply to each predefined set of process areas. The following sections describe the characteristics of each maturity level in detail.
Maturity Level 1 – Initial: Company has no standard process for software development. Nor does it have a project-tracking system that enables developers to predict costs or finish dates with any accuracy.
In detail we can describe it as given below:
At maturity level 1, processes are usually ad hoc and chaotic.
The organization usually does not provide a stable environment. Success in these organizations depends on the competence and heroics of the people in the organization and not on the use of proven processes.
Maturity level 1 organizations often produce products and services that work but company has no standard process for software development. Nor does it have a project-tracking system that enables developers to predict costs or finish dates with any accuracy.
Maturity level 1 organizations are characterized by a tendency to over commit, abandon processes in the time of crisis, and not be able to repeat their past successes.
Maturity Level 2 – Managed: Company has installed basic software management processes and controls. But there is no consistency or coordination among different groups.
In detail we can describe it as given below:
At maturity level 2, an organization has achieved all the specific and generic goals of the maturity level 2 process areas. In other words, the projects of the organization have ensured that requirements are managed and that processes are planned, performed, measured, and controlled.
The process discipline reflected by maturity level 2 helps to ensure that existing practices are retained during times of stress. When these practices are in place, projects are performed and managed according to their documented plans.
At maturity level 2, requirements, processes, work products, and services are managed. The status of the work products and the delivery of services are visible to management at defined points.
Commitments are established among relevant stakeholders and are revised as needed. Work products are reviewed with stakeholders and are controlled.
The work products and services satisfy their specified requirements, standards, and objectives.
Maturity Level 3 – Defined: Company has pulled together a standard set of processes and controls for the entire organization so that developers can move between projects more easily and customers can begin to get consistency from different groups.
In detail we can describe it as given below:
At maturity level 3, an organization has achieved all the specific and generic goals.
At maturity level 3, processes are well characterized and understood, and are described in standards, procedures, tools, and methods.
A critical distinction between maturity level 2 and maturity level 3 is the scope of standards, process descriptions, and procedures. At maturity level 2, the standards, process descriptions, and procedures may be quite different in each specific instance of the process (for example, on a particular project). At maturity level 3, the standards, process descriptions, and procedures for a project are tailored from the organization’s set of standard processes to suit a particular project or organizational unit.
The organization’s set of standard processes includes the processes addressed at maturity level 2 and maturity level 3. As a result, the processes that are performed across the organization are consistent except for the differences allowed by the tailoring guidelines.
Another critical distinction is that at maturity level 3, processes are typically described in more detail and more rigorously than at maturity level 2.
At maturity level 3, processes are managed more proactively using an understanding of the interrelationships of the process activities and detailed measures of the process, its work products, and its services.
Maturity Level 4 – Quantitatively Managed: In addition to implementing standard processes, company has installed systems to measure the quality of those processes across all projects.
In detail we can describe it as given below:
At maturity level 4, an organization has achieved all the specific goals of the process areas assigned to maturity levels 2, 3, and 4 and the generic goals assigned to maturity levels 2 and 3.
At maturity level 4 Sub-processes are selected that significantly contribute to overall process performance. These selected sub-processes are controlled using statistical and other quantitative techniques.
Quantitative objectives for quality and process performance are established and used as criteria in managing processes. Quantitative objectives are based on the needs of the customer, end users, organization, and process implementers. Quality and process performance are understood in statistical terms and are managed throughout the life of the processes.
For these processes, detailed measures of process performance are collected and statistically analyzed. Special causes of process variation are identified and, where appropriate, the sources of special causes are corrected to prevent future occurrences.
Quality and process performance measures are incorporated into the organizations measurement repository to support fact-based decision making in the future.
A critical distinction between maturity level 3 and maturity level 4 is the predictability of process performance. At maturity level 4, the performance of processes is controlled using statistical and other quantitative techniques, and is quantitatively predictable. At maturity level 3, processes are only qualitatively predictable.
Maturity Level 5 – Optimizing: Company has accomplished all of the above and can now begin to see patterns in performance over time, so it can tweak its processes in order to improve productivity and reduce defects in software development across the entire organization.
In detail we can describe it as given below:
At maturity level 5, an organization has achieved all the specific goals of the process areas assigned to maturity levels 2, 3, 4, and 5 and the generic goals assigned to maturity levels 2 and 3.
Processes are continually improved based on a quantitative understanding of the common causes of variation inherent in processes.
Maturity level 5 focuses on continually improving process performance through both incremental and innovative technological improvements.
Quantitative process-improvement objectives for the organization are established, continually revised to reflect changing business objectives, and used as criteria in managing process improvement.
The effects of deployed process improvements are measured and evaluated against the quantitative process-improvement objectives. Both the defined processes and the organization’s set of standard processes are targets of measurable improvement activities.
Optimizing processes that are agile and innovative depends on the participation of an empowered workforce aligned with the business values and objectives of the organization.
The organization’s ability to rapidly respond to changes and opportunities is enhanced by finding ways to accelerate and share learning. Improvement of the processes is inherently part of everybody’s role, resulting in a cycle of continual improvement.
A critical distinction between maturity level 4 and maturity level 5 is the type of process variation addressed. At maturity level 4, processes are concerned with addressing special causes of process variation and providing statistical predictability of the results. Though processes may produce predictable results, the results may be insufficient to achieve the established objectives. At maturity level 5, processes are concerned with addressing common causes of process variation and changing the process (that is, shifting the mean of the process performance) to improve process performance (while maintaining statistical predictability) to achieve the established quantitative process-improvement objectives.
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