What is Extreme Programming (XP)? - Definition from WhatIs.com Extreme Programming (XP) is a pragmatic approach to program development that emphasizes business results first and takes an incremental, get-something-started approach to building the product, using continual testing and revision. Kent Beck, author of Extreme Programming Explained: Embrace Change, developed the XP concept. According to Beck, code comes first in XP. However, Beck emphasizes that in order to write the code, you have to write a test for it first so that you will know when your code succeeds. Beck calls Extreme Programming a "lightweight methodology" that challenges the assumption that getting the software right the first time is the most economical approach in the long run. This was last updated in August 2008 Email Alerts Register now to receive SearchSoftwareQuality.com-related news, tips and more, delivered to your inbox. By submitting you agree to receive email from TechTarget and its partners. More News and Tutorials
Software Process Models Many process models I came across so far have their background in a certain engineering setup which I call "the happy engineering world". I called it this way, because in this "world" you design systems where requirements can be set up from the beginning, sub-components may be even available to a large extend and very often resources are not strictly limited. As an example may serve an airport traffic control system. However, there is also a quite different world and this is mostly forgotten by the preachers of process models. The spiral model would have been a solution too, however there are these nasty risk analysis phases which we did not want to do and which made not much sense in our situation. The Waterfall Model The waterfall model is believed to have been the first process model which was introduced and widely followed in software engineering. As programs became bigger the need for a better requirements phase, some more thoughts on the design, etc. were needed. The V Model
Agile Test Methodology Vs V Model The object of the article is to uncover the disadvantages of the traditional V model of testing over the Agile test methodology. In doing so we will cover the following points: What is V model? Advantages and disadvantages of V model.What is Agile Testing? V model V-model is a software development model that is based on the relationships between each phase of the development life cycle as described in a typical Waterfall model of software development and its associated phase of testing Agile Test Methodology Vs V Model Figure 1 The V-model involves building a logical V shape sequence where the testing techniques associated with the design are reflected as descending and are applied for the “verification” and connected to the requirements or specifications parts are reflected as ascending and are applied for “validation”. The V-Model is a Software life cycle model. It explains how you go from high level concept to released product. Advantages of V Model Disadvantages of V Model Agile Testing
The Death of the V-Model The V-Model of software development is widely in use today, especially in the defence industry. It’s a pity then, that it is fundamentally flawed, and that it is responsible for misleading project managers into thinking that the project they are about to undertake is well understood. The reality is that the more the V-Model is used as a tool to manage the software development process, the more likely that project is to fail. The following diagram is a typical representation of the V-Model. This model does have a number of good points, such as: It defines tangible phases of the process, and proposes a logical sequence in which these phases should be approached. However, this is as far as it goes. Let us take a look at the software development process for a moment. In the software development world, you can bet your last dollar that the plan will change. A second reason whey the V-Model fails, is in the testing phases, and has been illustrated by Brian Marick².
What Lifecycle? Selecting the Right Model for Your Project A cynical senior manager said, “It feels as if I’m stuck between the traditionalists and the agilistas. We can’t use phase-gate anymore, because it’s not ‘agile’ enough. And the last time, when that multisite project tried Scrum, they failed miserably. A project doesn’t have to use just one lifecycle. But too few project and program managers know about their choices for lifecycles. You might think that there are only two extremes of lifecycles: the serial lifecycles, of which waterfall is one example; and the agile lifecycles, of which Scrum might be the most adopted example. Figure 1 — A continuum of lifecycles. As you can see, you have many options for which lifecycle to use when in a project . What do the terms mean? If you are accustomed to looking at Gantt charts, Figure 2 shows what the lifecycles look like on a Gantt. Figure 2 — A Gantt-like look at lifecycles. Here’s a brief explanation of the terms. An iterative lifecycle is one where you prototype pieces of the product. 1. 2.
Life cycles: methodologies compared History The "waterfall model", documented in 1970 by Royce was the first publicly documented life cycle model. The model was developed to help cope with the increasing complexity of aerospace products. Methods Life cycle models describe the interrelationships between software development phases. spiral modelwaterfall modelthrowaway prototyping modelevolutionary prototyping modelincremental/iterative developmentreusable software modelautomated software synthesis Because the life cycle steps are described in very general terms, the models are adaptable and their implementation details will vary among different organizations. Learn A software life cycle model depicts the significant phases or activities of a software project from conception until the product is retired. Evaluate Spiral Model The spiral model is the most generic of the models. Waterfall Model The least flexible and most obsolete of the life cycle models. Throwaway Prototyping Model Evolutionary Prototyping Model
WATERFALL vs. AGILE METHODOLOGY « Agile Introduction For Dummies There is no IT meeting that does not talk and debate endlessly about Waterfall vs. Agile development methodologies. Feelings run strong on the subject with many considering Agile ‘so of the moment’, just so right, while Waterfall is thought to be passé! Waterfall A classically linear and sequential approach to software design and systems development, each waterfall stage is assigned to a separate team to ensure greater project and deadline control, important for on-time project delivery. 1. 2. 3. 4. 5. However, in case a glitch should result, changing the software is not only a practical impossibility, but means one has to go right back to the beginning and start developing new code, all over again. 1. 2. 3. 4. To synopsise the difference between the two, one can say the classic waterfall method stands for predictability, while Agile methodology spells adaptability. 1. 2. 3. 4. Like this: Like Loading... Tags: agile, comparison, waterfall
Agile Methodology - Agile Methodologies for Software Development The various agile methodologies share much of the same philosophy, as well as many of the same characteristics and practices. But from an implementation standpoint, each has its own recipe of practices, terminology, and tactics. Here we have summarized a few of the main methodology contenders: Scrum Scrum is a lightweight agile project management framework with broad applicability for managing and controlling iterative and incremental projects of all types. In Scrum, the "Product Owner" works closely with the team to identify and prioritize system functionality in form of a "Product Backlog". Scrum has been proven to scale to multiple teams across very large organizations with 800+ people. Lean and Kanban Software Development Lean Software Development is an iterative agile methodology originally developed by Mary and Tom Poppendieck. Eliminating Waste Amplifying Learning Deciding as Late as Possible Delivering as Fast as Possible Empowering the Team Building Integrity In Seeing the Whole
Project Lifecycle Models: How the differ and when to use them Business eSolutions provides System Development Project Management services, Problem Project Diagnostic and Recovery services and Project Management Training and Facilitation courses covering strategy, project management, project estimating, business requirements, risk management and quality assurance. We can help you define a lifecycle methodology customized to your organizational strengths and development risks. Our mission is to help our clients produce quality systems on time and on budget. Project lifecycle models are not interchangeable. To deliver a quality system, it's critical to know the risks facing your project and to use a model that reduces those risks. Pure Waterfall • Spiral • Modified Waterfall • Evolutionary Prototyping • Code-and-Fix Staged Delivery • Evolutionary Delivery • Design-to-Schedule • Design-to-Tools • Off-the-Shelf What model do you use? Pure Waterfall This is the classical system development model. Spiral Determine objectives, alternatives and constraints.
Scrum Methodology & Agile Scrum Methodologies What is SCRUM? Contents Introduction SCRUM is a loose set of guidelines that govern the development process of a product, from its design stages to its completion. It aims to cure some common failures of the typical development process, such as: Chaos due to changing requirements - the real or perceived requirements of a project usually change drastically from the time the product is designed to when it is released. SCRUM has been successfully employed by hundreds of different companies in many different fields, with outstanding results. You will find many similarities between SCRUM and Extreme Programming, but one of the major differences is that SCRUM is a fairly general set of guidelines that govern the development process of a product. SCRUM Values The SCRUM values are derived from the Agile values of software development. The SCRUM Process Figure 1: General SCRUM Process The scrum process has 3 main phases. Planning In this phase, the project is planned and high-level design decisions are made. Closure