Software designing methodology

The decision to choose a methodology depends upon the project requirements and time frame. The development work is divided into distinct phases according to the development methodology chosen. It may follow either an iterative approach or end-to-end completion in one go according to the project requirements. The methodologies ensure a smooth software development experience while fulfilling project requirements. The software development methodology is concerned only with the planning aspects of the software development and hence it acts as a framework that is used to design, plan, and guide the software development process.

If the SDM are either not in place or are not implemented properly, various problems start coming up as the development works progress.

This may also lead to the development of a software application with a lot of defects. Software with various defects may damage the reliability and image of the company. The waterfall model is considered the most basic and traditional software development methodology. The waterfall model consists of phases requirements, design, implementation, verification, maintenance that are carried out in sequence and focus on specific tasks for each phase.

Each phase must be completed before the start of the next phase. Once a phase is complete, there is no going back to that phase for modification. The waterfall method is easy to manage due to its sequential nature. A method can be defined as a systematic procedure for a set of activities. Thus, from these definitions, a met hodology will encompass the methods used within the methodology.

Different methodologies can support work in different phases of the system life cycle, for example, planning, analysis, design and programming, testing and implementation. Svoboda de veloped the idea of a methodology further by proposing that there should be at least four components: a conceptual model of constructs essential to the problem, a set of procedure suggesting the direction and order to proceed, a series of guidelines identifying things to be avoided, and a collection of evaluation criteria for assessing the quality of the product.

The conceptual model is needed to direct or guide the designers to the relevant aspects of the system. The set of procedure provides the designer a systematic and logical set of activities to begin the design task. The evaluation criteria provide an obje ctive measurement of the work done against some established standard or specifications. A software design methodology can be structured as comprising of the software design process component and the software design representation or diagrammatic component.

The process component is based on the basic principles established in the methodolog y while the representation component is the "blueprint" from which the code for the software will be built.

It should be noted, that in practice, the design methodology is often constrained by existing hardware configuration, the implementation language,the existing file and data structures and the existing company practices, all of which would limit the solution space available to develop the software.

The evolution of each software design needs to be meticulously recorded or diagramed, including the basis for choices made, for future walk-throughs and maintenance. Design is a formation of a plan of activities to accomplish a recognized need. The need may be well defined or ill defined. When needs are ill-defined, it is likely due to the fact that neither the need nor problem has been identified. The design process is a process of creative invention and definition, it involves synthesis and analysis, and thus, is difficult to summarize in a simple design formula.

Design is an applied science. In a software design problem, a number of solutions exist. The designer each word "designer" can also refer to "designers" must plan and execute the design strategy taking into account certain established design practices.

The designer often has to fall back on previous experience gained and has to study the existing software methodologies designed by others, to analyze their advantages and disadvantages.

It is useful also to review the basic parameters, especially the requirements and system specifications. A designer must constantly improve and enrich his store of design solution.

The development of design alternatives should be a regular design activity aimed at seeing the most rational solution. In the design of software, often there are different design methodologies that can be used to derive a software solut ion, this is called the design degree of freedom. A design solution can also have several degrees of freedom, which implies that there is possibly at least one solution in the solution space, often there is more than one solution. It must be noted that there are no unique answers for design.

However, that does not imply that any answer will do. Some solutions are more optimal than others. A design is subject to certain problem-solving constraints, for example, in a vacation design problem, the const raints are money and time. Note also that there are constraints on the solutions, for example, users must be satisfied. Then in synthesis, it is necessary to begin with the solution of the main design problems and separate secondary items from the main ones.

Successful design often begins with a clear definition of the design objectives. While in analysis and evaluation, the designer using these knowledge and simple diagrams, makes a first draft of the design in the form of diagrams.

This has to be t horoughly analyzed to verify that it meets the design objectives and that it is adequate but not over designed. A systematic approach is useful only to the extent that the designer is presented with a strategy that he can use as a base for planning the r equired design strategy for the problem at hand.

A design problem is not a theoretical construct. Design has an authentic purpose - the creation of an end result by taking definite action or the creation of something having physical reality. The design process is by necessity an iterative one. The software design should describe a system that meet the requirements. It should be thorough, in-depth, complete and use standardized notations to depict the structure and systems.

According to Ford , p. If any of the two scenarios is true, then DevOps might be what your business needs. In a nutshell, DevOps is a method for improved collaboration and tighter integration. Developers and operations professionals had different objectives and worked on different floors or even buildings. What makes DevOps so brilliant is that it brings the two teams together.

Thanks to the collaboration between developers and operations professionals, the software can be tested faster and more reliably.

If your business objectives are well-defined and narrow, then the Rapid Application Development Methodology RAD is something you might want to implement. The RAD approach came out of the need to deliver applications in a very short amount of time. Here, rapid development is achieved by using component-based construction.

There's high user involvement. Until the user approves that all the requirements are met, the user design and construction stages can be repeated. Looking to develop your software in one-third of the time with a very limited budget? Look to Lean! Across industries, the Lean model is used to reduce development costs, improve quality, increase productivity, and improve customer satisfaction.

In short, Lean development is the application of Lean principles to development. It has 7 main principles, including:. Pros: The primary benefit of agile software development is that it allows software to be released in iterations. Iterative releases improve efficiency by allowing teams to find and fix defects and align expectation early on.

They also allow users to realize software benefits earlier, with frequent incremental improvements. Cons: Agile development methods rely on real-time communication, so new users often lack the documentation they need to get up to speed. They require a huge time commitment from users and are labor intensive because developers must fully complete each feature within each iteration for user approval.

Agile development methods are similar to rapid application development see below and can be inefficient in large organizations. Programmers, managers, and organizations accustomed to the waterfall method see below may have difficulty adjusting to an agile SDLC. So a hybrid approach often works well for them. Get the Agile Security Manifesto.