Agile Methodolgy

March 28, 2017

Agile Methodology

Before starting with Agile, let's cover some basics.

SDLC (Software Development Life Cycle)

. The Software Development Life Cycle is a process that ensures good software is built. SDLC is a process used by software industry to design, develop and test high-quality software.
. The life cycle defines a methodology for improving the quality of software and the overall development process.
. The systems development life-cycle concept applies to a range of hardware and software configurations, as a system can be composed of hardware only, software only, or a combination of both.

Different types of projects have different requirements. Therefore, it may be required to choose the SDLC phases according to the specific needs of the project. These different requirements and needs give us various software development approaches to choose from during software implementation.

Types of Software developing life cycles (SDLC)

§ Waterfall Model

§ V-Shaped Model

§ Big Bang Model

§ Spiral Model (SDM)

§ Iterative Model

§ Agile Model

Waterfall Model:-

Waterfall approach was the first SDLC Model to be used widely in Software Engineering to ensure success of the project. In "The Waterfall" approach, the whole process of software development is divided into separate phases, the outcome of one phase acts as the input for the next phase sequentially.

Agile Model:-

Agile methodology promotes continuous iteration of development and testing throughout the software development lifecycle of the project. It advocates adaptive planning, evolutionary development, early delivery, and continuous improvement, and it encourages rapid and flexible response to change. Agilists propose alternatives to waterfall, or traditional sequential development.

Agile Model	Waterfall Model
Agile method proposes incremental and iterative approach to software design	Development of the software flows sequentially from start point to end point.
The agile process is broken into individual models that designers work on.	The design process is not broken into an individual models
The customer has early and frequent opportunities to look at the product and make decision and changes to the project	The customer can only see the product at the end of the project
Agile model is considered unstructured compared to the waterfall model	Waterfall model are more secure because they are so plan oriented
Small projects can be implemented very quickly. For large projects, it is difficult to estimate the development time.	All sorts of project can be estimated and completed.
Error can be fixed in the middle of the project.	Only at the end, the whole product is tested. If the requirement error is found or any changes have to be made, the project has to start from the beginning
Documentation attends less priority than software development	Documentation is a top priority and can even use for training staff and upgrade the software with another team
Every iteration has its own testing phase. It allows implementing regression testing every time new functions or logic are released.	Only after the development phase, the testing phase is executed because separate parts are not fully functional.
Testers and developers work together	Testers work separately from developers
At the end of every sprint, user acceptance is performed	User acceptance is performed at the end of the project.

Product owner: In Agile process product owner will decide all the requirements for a software. Product owner is a scrum development role for a person who represents the business or user community and is responsible for working with the user group to determine what features will be in the product release.

Product Backlog: All the user requirements are saved in product backlog. Product owner will decide which user story's he/she wants to complete first. Then according to that their will be a sprint meeting.

What is Sprint Meeting?

In sprint meeting all the team member(developers, testers) will participate for each release of a product that is called sprint.

In sprint meeting all the team members understand the modules and requirements and give their estimate for each task.

Sprint: Sprint is of 1-2weeks in which we complete 4-5 user stories according to software priorities.

Scrum: Scrum is the most popular way of introducing Agility due to its simplicity and flexibility. Scrum is of multiple sprints in which we complete multiple user stories.

Scrum Master: Scrum Master keeps the track of the Software Product. Scrum Master conduct a daily stand up meetings with all the team members everyday for 20-30 mins.

The scrum master asks the team members these three questions:

1. What did you do yesterday?

2. What will you do today?

3. Are there any impediments in your way?

Sprint BackLogs: The sprint backlog is a list of tasks identified by the Scrum team to be completed during the Scrum sprint. During the sprint planning meeting, the team selects some number of product backlog items usually in the form of user stories, and identifies the tasks necessary to complete each user story. All the team members give their estimates how many hours will take to complete their tasks.

Sprint BurnDownChart: The sprint burndown chart is a public displayed chart showing remaining work in the sprint backlog. Updated every day, it gives a simple view of the sprint progress.

Retrospective meeting:

After the release of each sprint all the team members discuss how the sprint was. How can we improve our product quality.

There are various methodologies that are collectively known as agile, as they promote the values of the agile manifesto and they are consistent with the above principles. The most popular ones are:

Scrum is also an agile development method, which concentrates particularly on how to manage tasks within a team-based development environment. Scrum is the most popular and widely adopted agile method – I think because it is relatively simple to implement and addresses many of the management issues that have plagued IT development teams for decades. Just keep in mind: Scrum is a project management framework, not a development method.

XP (Extreme Programming) is a more radical agile methodology, focusing more on the software engineering process and addressing the analysis, development and test phases with novel approaches that make a substantial difference to the quality of the end product.

DSDM is probably the original agile development method. DSDM was around before the term ‘agile’ was even invented, but is absolutely based on all the principles we’ve come to know as agile. DSDM seems to be much less well-known outside of the UK.

DSDM is probably the most complete agile methodology, whereas Scrum and XP are easier to implement and complementary because they tackle different aspects of software development projects and are both founded on very similar concepts.

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.

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.

Pros

. good and organized involvement of customer and stake holders

. easier to stay within the 80%

. continuous feedback

. more flexible to changes

. team motivation

. very transparent when tracing progress

. makes it more obvious where delays come from (think unclear requirements)

Cons

. Team needs to embrace the methodology. this needs a very open, communicative mindset.

. easy to slack and let discipline go

. very high pressure on the product owner scrum role