Several major development model differences and linkages

Preface

In software engineering, a software development methodology (also known as asystem development methodology software development life cycle, software development process, Software process) is a split Ting of software developmentwork into distinct phases (or stages) containing activities with the intent of better planning and management. It is often considered a subset for the systems development life cycle. The methodology may include thepre-definition of specific deliverables and artifacts, that is created and completed by a P Roject team to develop or maintain an application. (From Wikipedia)

The software development model includes waterfall model, rapid prototyping model, incremental model, spiral model, fountain model. Although these models have been popular for many years and are well known, not a model is suitable for any project, but rather a different development process based on specific projects. Let's look at the differences and linkages between the various models.

Body

1. Waterfall Models: The waterfall model is a sequential development approach, in which development is seen as flowing steadily downwards (like a waterfall) through several phases. (quoted from Wikipedia)

Analysis: The development process is one after the other, and only the next stage is completed at the previous stage.

2. Rapid Prototyping model: Software prototyping, is the development approach of activities during software development, the creation of pro Totypes. (quoted from Wikipedia)

Analysis: Each project into a small piece of a small piece to do, the beginning of the project may be users of the requirements of the description is not clear, so developers continue to develop models to see whether to meet the needs of users, and then constantly modify until the user is satisfied. This allows the user to participate in the entire development process, which minimizes user dissatisfaction with the project. Partially created prototypes can be directly enabled, thus speeding up the software development process and saving costs due to fewer modifications after the project is completed.

3. Incremental model: Various methods is acceptable for combining linear and iterative systems development methodologies, with the prim ary objective of each being to reduce inherent project risk by breaking a project into smaller segments and providing more Ease-of-change during the development process (quoted from Wikipedia)

Analysis: First developed a part of the function, and then constantly according to the needs of the development of additional functions, constantly based on user feedback to decide whether to retain the function, and then continue to add functionality.

4. Helical Model: Spiral model, which combines some key aspect of the waterfall model and rapid prototypingmethodologies, in an Effo RT to combine advantages of top-down and bottom-up concepts. (quoted from Wikipedia)

Analysis: Risk assessments are conducted before each stage to minimize risk and incorporate a rapid prototyping model.

5. Fountain Model: It is a model based on user's demand and driven by object, which is mainly used to describe the object-oriented software development process (quoted from Baidu Encyclopedia)

Analysis: Iterations between individual development processes, and iterations between individual work steps within a single phase.

Summarize

Difference: 1. The waterfall model and the Helix model are all followed by one step after another, while the other three models are constantly cross-cutting, and when the project is completed it is constantly discovering new requirements, and then it is developed again.

2. Rapid prototyping Model user engagement is very high, the user satisfaction is high, greatly reduce the risk of large rework, and similar waterfall model if the initial understanding of the need is unclear, then need to correct the previous error, rework rate is relatively high.

3. The Helix model can significantly reduce the risk of the project relative to the waterfall model, since the Helix model carries out risk assessments on a per-time. Suitable for large-scale project development.

4. Incremental models can be delivered in a relatively short period of time relative to other models. As long as a part of the function can be developed first. And there is plenty of time to customize the right product for user feedback.

5. Incremental models in contrast to the waterfall model or the rapid development model submission project, it is delivered in batches, and the waterfall model is a one-time delivery.

Contact: 1. Waterfall model is similar to the development of spiral model, it is the first stage, then another stage.

2. Both the rapid prototyping model and the fountain model iterate through each phase.

3. The incremental model is the segmented waterfall model, and the fountain model is based on the waterfall model as the main line.

sentiment

This paper analyzes the characteristics of these five models, each of which has its own advantages and disadvantages, and the most important is to select the appropriate model in the specific project.

2016-03-07 00:40:26

Several major development model differences and linkages