The life cycle of software is the time period from the moment a decision is made to develop a product until its end-of-life. To make the design, development and release of a new high-quality product a little easier, we created software life cycle models.
The decisive factor for determining the most appropriate methodology is the design requirements. Next, let’s take a closer look at the most popular models in software development.
The essence of the incremental methodology is that software is created in several increments (modifications), but linearly. Thanks to such a system, the improvement of the software product is carried out continuously according to plan until the moment until the software life cycle comes to an end.
The requirements for the project are voiced before starting work, then the creation process is carried out sequentially, where each version is a finished product, ready to work.
• You can view the risks associated with costs and deadlines;
• The customer of the product can comment on each version of it;
• The client gets used to the new methodology over time.
• The structure of the system can be broken with constant updates;
• For iterations to stand out, a functional system should be defined early in the life cycle;
• The implementation schedule may not be met due to limited resources (material, executive).
This software development model implies the assembly of different approaches. This includes a series of product approaches that focus on an iterative model, as well as dynamic requirements articulation and implementation through the seamless interaction of self-organized multidisciplinary teams.
Each individual iteration is a small project. One of the leading ideas of the agile model is a face-to-face interaction between the customer and the development team.
• The risk is minimized;
• More simplified work with documents;
• Decisions are made quickly through constant communication.
• Very rarely, the model is used to carry out large projects;
• Many conversations and meetings that affect the duration of software development;
• Due to the constantly changing requirements, it is difficult to plan the work.
The essence of the model is that each stage is carried out once, one after the other. To proceed to the next phase, you must completely complete the previous one.
• All phases of the project are strictly regulated and carried out in a clear sequence;
• Requirements for the project do not change throughout the entire cycle;
• Strictly fixed execution of all stages of the project allows you to plan resources and completion dates.
• Testing is carried out from the middle of the project;
• Since the requirements are immutable and must be clearly articulated, it is often difficult to write them;
• The user cannot be sure of the quality of the product until the complete completion of its development.
V- SHAPED MODEL
This model is a kind of modified version of the waterfall methodology, as it helps to get rid of the shortcomings shown earlier.
Its essence is complete control over the processes at all stages of development in order to make sure that it is already possible to move on to the next stage. Testing begins at the stage of formulating requirements.
• Improved time management within quality assurance organizations;
• Process of execution in strictly regulated stages;
• Low risk and elimination of potential bugs at the initial stages thanks to early testing.
• Lack of actions analyzing risks;
• Inability to adapt to new customer requirements;
• The development process takes a long time (sometimes even years). As a result, the product loses its relevance for the customer.
In this model, the software life cycle is depicted as a spiral. It begins at the stage of writing a plan and creates the so-called loops for the implementation of each next stage.
Thus, at the end of each round, we get a complete prototype that has passed testing and complements the entire assembly. If this prototype meets all the requirements, it is considered ready for release.
• Design flexibility;
• Sufficient attention is paid to the risk management process;
• New functionality can be added at a later stage of development.
• More often used for large projects;
• Risk assessment at each stage entails rather high costs;
• The ability to continually leave feedback by the customer provokes updated iterations, which affects the timing of software development.
In the world of the IT industry, there are a huge number of different methodologies for the software development life cycle. Which one to give preference depends on the formulated requirements, product features and payment models. Each of the methodologies partially finds its reflection in others, but at the same time has its own individual, distinctive features. If you need a piece of free expert advice, you can always refer to the leading IT companies, like serokell.io.