The Agile System Development Life Cycle (SDLC). And invariably I found myself sketching one or more pictures which overview the life cycle for agile software development projects. I typically need one or more pictures because the scope of life cycles change - some life cycles address just the construction life cycle, some address the full.
- Summary Of Agile Development Methodology
- Agile Software Development Pdf
- Agile Software Development Overview Template
What is Agile Methodology?
AGILE methodology is a practice that promotes continuous iteration of development and testing throughout the software development lifecycle of the project. Both development and testing activities are concurrent unlike the Waterfall model
Scrum Overview for Agile Software Development Scrum is an agile process most commonly used for product development, especially software development. Scrum is a project management framework that is applicable to any project with aggressive deadlines, complex requirements and a degree of uniqueness. Agile software development comprises various approaches to software development under which requirements and solutions evolve through the collaborative effort of self-organizing and cross-functional teams and their customer(s)/end user(s). Agile SDLC model is a combination of iterative and incremental process models with focus on process adaptability and customer satisfaction by rapid delivery of working software product. Agile Methods break the product into small incremental builds. These builds are provided in iterations. Benefits Agile Software Development. Agile came largely as a response to the flaws recognized in software development process that preceded it. The most common, waterfall, was heavily front loaded and focused on developing a long term development plan followed by the implementation of that plan.
The agile software development emphasizes on four core values.
- Individual and team interactions over processes and tools
- Working software over comprehensive documentation
- Customer collaboration over contract negotiation
- Responding to change over following a plan
In this Software Engineering tutorial, you will learn
Agile Vs Waterfall Method
Agile and Waterfall model are two different methods for software development process. Though they are different in their approach, both methods are useful at times, depending on the requirement and the type of the project.
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Agile Methodology
There are various methods present in agile testing, and those are listed below:
Scrum
SCRUM is an agile development method which concentrates specifically on how to manage tasks within a team-based development environment. Basically, Scrum is derived from activity that occurs during a rugby match. Scrum believes in empowering the development team and advocates working in small teams (say- 7 to 9 members). It consists of three roles, and their responsibilities are explained as follows:
- Master is responsible for setting up the team, sprint meeting and removes obstacles to progress
- The Product Owner creates product backlog, prioritizes the backlog and is responsible for the delivery of the functionality at each iteration
- Team manages its own work and organizes the work to complete the sprint or cycle
Product Backlog
This is a repository where requirements are tracked with details on the no of requirements(user stories) to be completed for each release. It should be maintained and prioritized by Product Owner, and it should be distributed to the scrum team. Team can also request for a new requirement addition or modification or deletion
Scrum Practices
Practices are described in detailed:
Process flow of Scrum Methodologies:
Process flow of scrum testing is as follows:
- Each iteration of a scrum is known as Sprint
- Product backlog is a list where all details are entered to get the end-product
- During each Sprint, top user stories of Product backlog are selected and turned into Sprint backlog
- Team checks for the daily work
- At the end of the sprint, team delivers product functionality
eXtreme Programming (XP)
Extreme Programming technique is very helpful when there is constantly changing demands or requirements from the customers or when they are not sure about the functionality of the system. It advocates frequent 'releases' of the product in short development cycles, which inherently improves the productivity of the system and also introduces a checkpoint where any customer requirements can be easily implemented. The XP develops software keeping customer in the target.
Business requirements are gathered in terms of stories. All those stories are stored in a place called the parking lot.
In this type of methodology, releases are based on the shorter cycles called Iterations with span of 14 days time period. Each iteration includes phases like coding, unit testing and system testing where at each phase some minor or major functionality will be built in the application.
Phases of eXtreme programming:
There are 6 phases available in Agile XP method, and those are explained as follows:
Planning
- Infrastructure Requirements
- Service Level Agreements and its conditions
Analysis
- Prioritize stories in Parking lot
- Define Iteration SPAN(Time)
- Resource planning for both Development and QA teams
Design
- Test Scenario preparation for each task
Execution
- Coding
- Execution of Manual test scenarios
- Conversion of Manual to Automation regression test cases
- End of Iteration review
Wrapping
- Regression Testing
- Develop new stories based on the need
- Process Improvements based on end of iteration review comments
Closure
- Training
- SLA Guarantee assurance
- Production Support
There are two storyboards available to track the work on a daily basis, and those are listed below for reference.
- This is a traditional way of collecting all the stories in a board in the form of stick notes to track daily XP activities. As this manual activity involves more effort and time, it is better to switch to an online form.
- Online tool Storyboard can be used to store the stories. Several teams can use it for different purposes.
Crystal Methodologies
Crystal Methodology is based on three concepts
- Chartering: Various activities involved in this phase are creating a development team, performing a preliminary feasibility analysis, developing an initial plan and fine-tuning the development methodology
- Cyclic delivery: The main development phase consists of two or more delivery cycles, during which the
- Team updates and refines the release plan
- Implements a subset of the requirements through one or more program test integrate iterations
- Integrated product is delivered to real users
- Review of the project plan and adopted development methodology
- Wrap Up: The activities performed in this phase are deployment into the user environment, post- deployment reviews and reflections are performed.
Dynamic Software Development Method (DSDM)
DSDM is a Rapid Application Development (RAD) approach to software development and provides an agile project delivery framework. The important aspect of DSDM is that the users are required to be involved actively, and the teams are given the power to make decisions. Frequent delivery of product becomes the active focus with DSDM. The techniques used in DSDM are
- Time Boxing
- MoSCoW Rules
- Prototyping
![Agile Software Development Overview Agile Software Development Overview](https://image.slidesharecdn.com/agilesoftwaredevelopmentoverview12315607340080862-1232174307743651-3/95/agile-software-development-overview-1231560734008086-2-16-728.jpg?cb=1232152755)
The DSDM project consists of 7 phases
- Pre-project
- Feasibility Study
- Business Study
- Functional Model Iteration
- Design and build Iteration
- Implementation
- Post-project
Feature Driven Development (FDD)
This method is focused around 'designing & building' features. Unlike other agile methods, FDD describes very specific and short phases of work that has to be accomplished separately per feature. It includes domain walkthrough, design inspection, promote to build, code inspection and design. FDD develops product keeping following things in the target
- Domain object Modeling
- Development by feature
- Component/ Class Ownership
- Feature Teams
- Inspections
- Configuration Management
- Regular Builds
- Visibility of progress and results
Lean Software Development
Lean software development method is based on the principle 'Just in time production'. It aims at increasing speed of software development and decreasing cost. Lean development can be summarized in seven steps.
- Eliminating Waste
- Amplifying learning
- Defer commitment (deciding as late as possible)
- Early delivery
- Empowering the team
- Building Integrity
- Optimize the whole
Kanban
Kanban originally emerged from Japanese word that means, a card containing all the information needed to be done on the product at each stage along its path to completion. This framework or method is quite adopted in software testing method especially in agile testing.
Scrum Vs Kanban
Summary Of Agile Development Methodology
Scrum | Kanban |
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Agile metrics:
Metrics that can be collected for effective usage of Agile is:
- Effort in hours which do not contribute to sprint goal
- Drag factor can be improved by reducing number of shared resources, reducing the amount of non-contributing work
- New estimates can be increased by percentage of drag factor -New estimate = (Old estimate+drag factor)
- Amount of backlog(user stories) converted to shippable functionality of sprint
- Time interval taken to complete daily build
- Bugs detected in an iteration or in previous iterations
- SDLC Tutorial
- SDLC Useful Resources
- Selected Reading
Agile SDLC model is a combination of iterative and incremental process models with focus on process adaptability and customer satisfaction by rapid delivery of working software product. Agile Methods break the product into small incremental builds. These builds are provided in iterations. Each iteration typically lasts from about one to three weeks. Every iteration involves cross functional teams working simultaneously on various areas like −
- Planning
- Requirements Analysis
- Design
- Coding
- Unit Testing and
- Acceptance Testing.
At the end of the iteration, a working product is displayed to the customer and important stakeholders.
What is Agile?
Agile model believes that every project needs to be handled differently and the existing methods need to be tailored to best suit the project requirements. In Agile, the tasks are divided to time boxes (small time frames) to deliver specific features for a release.
Iterative approach is taken and working software build is delivered after each iteration. Each build is incremental in terms of features; the final build holds all the features required by the customer.
Here is a graphical illustration of the Agile Model −
The Agile thought process had started early in the software development and started becoming popular with time due to its flexibility and adaptability.
The most popular Agile methods include Rational Unified Process (1994), Scrum (1995), Crystal Clear, Extreme Programming (1996), Adaptive Software Development, Feature Driven Development, and Dynamic Systems Development Method (DSDM) (1995). These are now collectively referred to as Agile Methodologies, after the Agile Manifesto was published in 2001.
![Agile Software Development Overview Agile Software Development Overview](https://www.imaginarycloud.com/blog/content/images/2018/12/Agile-method-1.png)
Following are the Agile Manifesto principles −
- Individuals and interactions − In Agile development, self-organization and motivation are important, as are interactions like co-location and pair programming.
- Working software − Demo working software is considered the best means of communication with the customers to understand their requirements, instead of just depending on documentation.
- Customer collaboration − As the requirements cannot be gathered completely in the beginning of the project due to various factors, continuous customer interaction is very important to get proper product requirements.
- Responding to change − Agile Development is focused on quick responses to change and continuous development.
Agile Vs Traditional SDLC Models
Agile is based on the adaptive software development methods, whereas the traditional SDLC models like the waterfall model is based on a predictive approach. Predictive teams in the traditional SDLC models usually work with detailed planning and have a complete forecast of the exact tasks and features to be delivered in the next few months or during the product life cycle.
Predictive methods entirely depend on the requirement analysis and planning done in the beginning of cycle. Any changes to be incorporated go through a strict change control management and prioritization.
Agile uses an adaptive approach where there is no detailed planning and there is clarity on future tasks only in respect of what features need to be developed. There is feature driven development and the team adapts to the changing product requirements dynamically. The product is tested very frequently, through the release iterations, minimizing the risk of any major failures in future.
Customer Interaction is the backbone of this Agile methodology, and open communication with minimum documentation are the typical features of Agile development environment. The agile teams work in close collaboration with each other and are most often located in the same geographical location.
Agile Model - Pros and Cons
Agile methods are being widely accepted in the software world recently. However, this method may not always be suitable for all products. Here are some pros and cons of the Agile model.
The advantages of the Agile Model are as follows −
Agile Software Development Pdf
- Is a very realistic approach to software development.
- Promotes teamwork and cross training.
- Functionality can be developed rapidly and demonstrated.
- Resource requirements are minimum.
- Suitable for fixed or changing requirements
- Delivers early partial working solutions.
- Good model for environments that change steadily.
- Minimal rules, documentation easily employed.
- Enables concurrent development and delivery within an overall planned context.
- Little or no planning required.
- Easy to manage.
- Gives flexibility to developers.
The disadvantages of the Agile Model are as follows −
Agile Software Development Overview Template
- Not suitable for handling complex dependencies.
- More risk of sustainability, maintainability and extensibility.
- An overall plan, an agile leader and agile PM practice is a must without which it will not work.
- Strict delivery management dictates the scope, functionality to be delivered, and adjustments to meet the deadlines.
- Depends heavily on customer interaction, so if customer is not clear, team can be driven in the wrong direction.
- There is a very high individual dependency, since there is minimum documentation generated.
- Transfer of technology to new team members may be quite challenging due to lack of documentation.