|
The business case for the project as part of their mandate, or in a separate document in order for the project (depending on the scale of the project), initiated the project before. The ownership of the executive sponsor. In many project methodologies such as PRINCE2 explicitly require a formal business case.
The business address of the high-level business needs that the project aims to solve. This includes the reasons for the expected economic benefits of the project, the opportunities (or the reason for rejecting the transfer of each option), the expected cost of the project, the gap analysis and the potential risks.
In almost all cases, it is not possible to keep the costs and risks of inactivity is accompanied by the difference (costs, risks, results, etc.) is not, and the proposed project.
In this, the justification of the project is derived.
The case will be reviewed at the beginning of the project (the go / no-go decision), and from time to time, the operation of the project (eg, section, or sub-boundaries), that:
1. The business case is still valid, ie, the business need still exists.
2. The project remains on track to a solution that enterprises need.
As a result of the review of the project may be terminated or modified in the future parts. The business is also subject to amendment if the review concludes that the business need for reduced or changed, it is the negative impact of the project.
The Business Case
Principles behind agile methods - The Agile Manifesto
Agile methods of family development processes, not a single approach to software development. 2001-ben, 17 prominent figures [1], the agile development (it is "easy methods") came to the snowbird ski resort in Utah to discuss ways of creating software, a lighter, faster, more human-centric way. They created the Agile Manifesto, is widely considered as the canonical definition of agile development and agile principles of the movement.
Some of the principles behind the Agile Manifesto are:
* Customer satisfaction is a rapid, continuous useful software
Working software is often shipped (seven months)
Working software is the most important measure of progress.
* Even late changes in requirements are welcomed.
* Close, daily cooperation with business people and developers
* Personal interviews with the best form of communication.
* The project is based on highly motivated individuals who should be entrusted
* The continued attention to technical excellence and good design.
* Simplicity
* Self-organizing groups
* Regular adaptation to changing circumstances
Publishers manifesto spawned a movement within the software industry known as agile software development.
2005-ben, Alistair Cockburn and Jim Highsmith gathered another group - management experts, this time - and wrote an addendum to the statement of the mutual PM.
Comparison with other methods
Agile methods are characterized as the opposite end of the "plan-driven" or "disciplined" methods. This distinction is misleading, since it means that the agile approach "unplanned" or "undisciplined." The distinction is not accurate to say that there is continuity in the method of "adaptive" and "forward." [3] Agile methods are the "adaptive" side of this continuum.
Adaptive methods focus on adapting quickly to changing realities. If the project needs change, an adaptive team changes as well. The team is difficult to describe adaptive exactly what will happen in the future. The remote date, the more adaptive method will be vague as to what will happen on that date. The adaptive report exactly what tasks to carry out team next week, but that is expected next month. When a release six months later, the adaptive team may only be able to release the report of the mission, and the statement of the expected value, or cost.
Predictive methods, it is planning to focus in more detail in the future. The team report, the exact predictive functions and tasks of the full length of the planned development process. Predictive variables of teams is difficult. The plan is generally optimized for the original purpose and the changing direction can cause completed work to be thrown away, and otherwise made over. Groups are often predictive of a change control board Institute, that only the most important changes into account.
Agile methods in common with a lot of "Rapid Application Development" techniques in 1980-as, as espoused James Martin and others (see RAD).
Contrary to the iterative development
Most agile methods share iterative development emphasis on building releasable software in short time periods. Agile methods differ from iterative methods, that the period should be measured, such as seven months, and the work carried out in a highly collaborative manner. Most agile methods also differ between the treatment period, they are strict timebox.
Unlike the waterfall model
This article or section does not cite references or sources.
You can help Wikipedia by introducing appropriate citations.
Agile development is less common in the waterfall model. In some eyes, the waterfall is lost, but as of 2004, this model continues to be the common use. The waterfall model is the most progress in the methods of stepping through requirements capture, analysis, design, coding and testing in a strict, pre-planned sequence. Progress is usually measured in the deliverable artifacts requirement specifications, design documents, test plans, code reviews and the like. The waterfall model is a result of significant efforts in the integration and testing towards the end of the cycle, a period, typically up to several months, a number of years. The size and the difficulty of the integration and testing efforts, one of the reasons for project failure waterfall. Agile methods to produce fully developed and tested features (only a very small part of the whole of) a few weeks or months. The focus is on obtaining the smallest workable piece of functionality that business value early, and continuous improvement / other functions throughout the life of the project.
If a project is deleted from the mid-point of the Waterfall project are often not in it. The Agile project has already delivered a number of codes will be used to drop out of the living environment.
The project is all there is the risk of changing requirements. The longer and more complex the project, the greater the risk of this occurring. Waterfall projects last year, there is a risk that it is too slow, what is needed in the current market - things have not changed significantly in 12 months. The structure is often verbose Waterfall project design document, each element of the client / project sponsor requirements. The production planning is a lengthy process (months), as well as some of this effort will be wasted - the customer wants only one year later. Change control mechanisms to be used to absorb the additional management and development time, adding that the overall costs. change is often viewed as disruptive to the project, and thus discouraged! Agile in the approach to recognize at the outset that not everything should be completed immediately, as we think we know now, it is unlikely that this will be a year away. Agile is the customer to prioritize the elements of the work then the following deliveries 1-2 iterations. Each iteration of the design phase, the customer, giving them the opportunity to reprioritise requirements - and the new requirements of the external world has been changed. [citation needed]
Some agile teams use the waterfall model is a small waterfall in the whole cycle is repeated for each iteration. Other groups, particularly Extreme Programming teams, work activities at once.
Contrary to the "cowboy coding"
Cowboy coding, that there is a defined method: team members what they feel right. Frequent reassessment of Agile development plans, with emphasis on the personal communications, and relatively little use of documents sometimes causes people to confuse it cowboy coding. Agile teams, however, do not follow it (and often very disciplined and rigorous) processes, agile approaches, the distinctive cowboy coding.
Like all other methods, skills and experience to the user (s) to the extent of success and / or abuse of such activity. The rigid controls and / or checks and balances embedded in a regularly offer greater levels of accountability in the process of the user (s). This is the degradation of a well-planned procedures, that the activities are often the Cowboy coding.
Suitability of agile methods
Although agile methods differ from the practices that have the same characteristics, including iterative development, and a focus on interaction, communication, and the decline of resource-intensive intermediate artifacts. (Cohen et al., 2004) [5] The suitability of agile methods in general can be examined from several perspectives. A product perspective, agile methods is much better, if the requirements of the emerging and fast-changing, they are less suitable for the system to a high critical reliability and security requirements, but there is no complete agreement on this issue (Cohen et al., 2004). [5] of the organizational point of view, the capacity can be assessed by examining the three most important aspects of the organization: the culture, people, and communication. In relation to this area a number of key success factors have been identified (Cohen et al., 2004) [5]:
* A culture of the organization should support the negotiation
* The people must be trusted
* Fewer, but more competent people
* Organizations should take the developers to the
* Organizations need to have an environment that fosters rapid communication with the members of the group
The most important factor is likely to project size (Cohen et al., 2004). [5] The size of the increase in personal communications will become more difficult. It is therefore better suited to agile methods, the project team is small, less than 20-40 people.
In order to determine the suitability of individual agile practices a much more sophisticated analysis is required. The method, for example, a so-called DSDM suitability filter 'for this purpose. In addition, the Crystal family methods criteria, how to select the method for a given project. The selection is based on project size, the critical and priority. However, other agile methods such a clear means to evaluate the project.
Some agile methods like DSDM and Feature Driven Development (FDD), it is claimed that the universally predefined solutions, which means that it should be used in any agile software development project, taking into account the situational characteristics (Abrahamsonn et al., 2003). [6]
A comparison of agile methods will be seen to support the various phases of the software development life cycle at different rates. This unique characteristic of agile methods can be used as the selection criteria for the selection of candidates agile methods.
Agile development has been widely documented (see Experience Reports, below, as well as Beck [7] pg. 157, and Boehm and Turner [8] pg. 55-57), works well as a small (<10 developers) co-located teams. Agile development is expected to be especially suitable for groups facing the unpredictable and rapidly changing requirements. Although there are some successful experience in the agile development team in addition to these parameters, and that too little experience to draw firm conclusions reported in April 2005.
Agile Development on the applicability of the scenario is open to question:
* Large-scale development efforts (> 20 developers.) Scaling strategies are described. [9]
* Distributed development efforts (non-co-located teams). Strategies have already been described in Bridging the Distance [10], and using an Agile Offshore Software Development Process [11]
* Mission-critical and life efforts
* Management and control company cultures
Boehm and Turner's risk-based approach
Barry Boehm and Richard Turner suggest that risk assessment should be used for the selection of adaptive ( "agile") and predictive ( "plan-driven") methods. [8] The authors suggest that the continuum on both sides, their home ground:
Agile home ground:
* Low critical
* Senior developers
* Requirements change very often
* There are few developers
* Culture flourishing in the chaos
Plan-driven home ground:
* High criticality
* Junior developers
* The change in low -
* A large number of developers
* Culture needs to
The analysis of the project against those of the home grounds, the risk of using agile or plan-driven methods can be determined.
Adapting to agile methods
The method should be flexible enough that the adjustment of the project implementation. There are three main questions that the subject agile adaptation methods: the suitability of agile methods (in general, and in particular), tailoring the method, and finally, project management support.
Agile methods and method tailoring
In literature, various aspects of the method refers to the concept of adaptation, including the 'method tailoring', 'method fragment adaptation' and 'situational method engineering. Method adapted to be determined:
The process or capability in which human agents through responsive to change and the dynamic interplays between contexts, intentions, and the method of determining system development approach to fragments of a specific project situation. [12]
Potentially, almost all agile methods are suitable for tailoring the method. Even the DSDM method is used for that purpose, and has been designed in conjunction with the CMM. [6] The situation may be regarded as a distinctive feature of the appropriateness of agile methods and traditional software development methods, the latter is much more rigid and rule fairly. The practical implication is that agile methods allow teams to adapt working practices according to the needs of the individual projects. Practice of specific activities and products that are part of the method. In a more extreme level, the philosophy of the method, a number of principles which could be adapted (Aydin, 2004) [12].
In the case of XP, the method is that it is necessary to make adjustments. One of the fundamental ideas of XP, that there is no process that fits all projects, but practices should be designed to the needs of individual projects. There are no reports of experience with all the XP practices were adopted. Instead, a partial adoption of XP practices, as Beck (Kent Beck), has been reported several times. [13]
A distinction should be made to adapt the method of static and dynamic method adaptation. [14] The basic assumption behind static method adaptation is that the project is given at the beginning of a project, and will continue with the implementation of the project. The result is a static definition of the project. Given this definition, route maps can be used in order to determine which of the structured method fragments should be used in the project, a pre-determined criteria. Dynamic method adaptation, in contrast, assumes that projects are developed in context. The emerging context means that the project is to address emerging factors appropriate conditions, but not predictable, and thus may occur in advance. This also means that the project is not constant, but varies in the implementation of the project. In this case, the standard road maps can not be used. The practical implication of dynamic method adaptation is that project managers often have to modify structured fragments or even innovate new fragments, during the execution of the project (Aydin et al, 2005).
Agile methods and project management
Agile methods differ greatly, as they are, project management. Some methods are supplemented with guidelines on project management, but usually not in full support. [6]
PRINCE2 has been suggested as an appropriate, complementary project management system.
History
The modern definition of agile software development evolved in the mid-1990s as a response to the "heavyweight" methods, as characterized by a highly regulated, regimented, micro-managed use of the waterfall development model. The use of these processes from the waterfall model was the bureaucratic, slow, humiliating, and contradicted by the way that software engineers to work effectively.
One may be that the iterative and agile development methodologies to return to see the early history of software development practice.
Initially, agile methods so-called "easy methods." 2001-was a prominent member of the snowbird community met and agreed to "agile methods." Later, some of those people in the agilis Alliance, a non-profit organization that promotes rapid development.
Early agile methods of scrimmage before the 2000-containing (a treatment) (1986), Crystal Clear, Extreme Programming (1996), Adaptive Software Development, Feature Driven Development, and DSDM (1995).
Extreme Programming, while this would not have been the first method is inarguably a popular agile agile methods. Extreme Programming was created by Kent Beck in 1996-a way to rescue the struggling Chrysler Comprehensive Compensation (C3) project. Although the project is finally canceled, Ron Jeffries, the method is refined, full-time coaching XP, Ward Cunningham, the public debate on Portland Pattern Repository wiki Beck and the further work, including a book in 1999. Elements of Extreme Programming appear to be based on Ward Cunningham's Episodes scrimmage and sample language.
Agile methods
Some well-known agile software development methods:
* Extreme Programming (XP)
* Scrimmage
* Agile Modeling
* Adaptive Software Development (ASD)
* Crystal Clear Crystal, and other methods
* Dynamic Systems Development Method (DSDM)
* Feature Driven Development
* Lean software development
* Agile Unified Process (AUP)
* Dialogue-Driven Development aka d3
Other approaches:
* Agile Documentation
* ICONIX
* The Microsoft Solutions Framework (MSF)
* Agile Data Method
* Database refactoring
Examples of the use of agile principles, not software activities:
* Lean Manufacturing
Reviews
Agile development is sometimes criticized the cowboy coding. Extreme Programming initial buzz and controversial tenets, such as pair programming and continuous design, in particular, attracted criticism, as McBreen and Boehm and Turner. However, the review also considered the experts of the misunderstanding about agile Agile Development.
In particular, Extreme Programming is to review and critique by Matt Stephens' Extreme Programming Refactored.
Reviews of the following:
* The lack of adequate structure and the required documentation
* Only the most senior-level developers
* It takes insufficient software design
* Claim too much cultural change to adopt
* Can lead to difficult contractual negotiations
The criticisms regarding insufficient software design and lack of documentation dealing with the agile modeling method, which can easily be tailored to the agile processes, such as the XP.
|
