Top-Down Versus Bottom-Up Analysis

Top-Down versus Bottom-Up Analysis

Although, both development processes can be used to analyze and develop a whole project. There are many existing differences between both development models. A top-down analysis usually starts by reviewing a project and its functional areas, as a whole, without much detailed information. During the process, specific areas of interest are decomposed into more detailed views or cells of information, which are examined and documented to better understand the project at hand. For example, a complete cell phone device is taken apart to study its new technology features. During the study process, each component is examined individually and any observations made are recorded or documented. The purpose is to figure out the functions of each part and how they work together. On the other hand, the bottom-up method begins by collecting the cell phone various components and trying to figured out how they work, look, and how to best assemble them together, so they can perform their normal functions.

Additionally, the top-down process has many advantages and disadvantages including the fact that it is very extensive and provides a great amount of information, as many processes are repeated. The process provides many different perspectives concerning work flow, performance, resource usage, issues, and alternative approaches to handle and resolve each situation. Once the system is established, it only requires periodic revisions and upgrades to maintain. However, the top-down analysis requires extra work, time, resources, and active communication with senior management to run smoothly.

Alike the top-down analysis, the bottom-up development has few advantages and disadvantages. The bottom-up analysis is less complex, faster to implement, and inexpensive, as it concentrates on the operational needs of its sponsor, which reduces the time, resources, and amount of work necessary to accomplish a project. However, as the project analysis is very narrow, many different anomalies can result including work redundancy and instability within other operational areas, which were not included during the initial evaluation. Please, see picture 18.3 to have a visual idea about both methods.

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