System Design is crucial to showcase the System's architecture used for the business. System Design is essential to implement the interfaces and the data flow to satisfy all the requirements of the System. Therefore a good strategy should be followed while designing the System.
A good System Design is to arrange all the modules so that the development or updation is more straightforward. A System Design strategy builds an optimal roadmap for the same. A good strategy reduces the complexity and helps you maintain the scalability of your system design. The analyst or the system design strategist is supposed to write the proper instructions at each step to make it easier for the developer to write the code for implementing the System.
The strategist's instructions should specify how the developer should write the code and fit all the modules together.
The strategy for a perfect System Design is made by keeping all the future and current requirements of the product or System So that there is the least number of changes required after the developer has written the code for the System.
System Design is essential in most companies, and the interviewers try to judge the strategies you follow to design the Systems in your projects.
Good System Design Strategy considers all the factors from the core architecture to the modules included in the product.
One of the importances of the System Design Strategy is that it lets you understand the pre-existing codes for any System implemented using the same System Design.
Following is the list of three approaches to perform the System Design:
1. Structured Design Approach
The structured Design approach breaks down the problem into more superficial elements and designs the system by rearranging them in an organized manner. The modules in this approach are arranged to reduce the cohesion between them.
2. Function Oriented Design Approach
In this approach, the subsystems performing each unique task are represented in the form of functions instead of simpler elements. The complete system is just the graph of all the parts combined. Unlike the Structured Design approach, the Function oriented approach works on inputs instead of the state. Also, this allows better data flow among all the functions compared to the data flow in different elements.
3. Object-Oriented Design Approach
This design approach is entirely different and has nothing in common with the two techniques discussed above. As per the name, this approach deals with objects and classes. All the tasks in this approach are defined as classes, and the strategy revolves around the objects of these classes and their characteristics. This approach deals with the objects and groups them into the class based on their attributes. After grouping objects, the relationships between the classes are defined while arranging them in a systematic hierarchical order.
One can use these three techniques or approaches to create the System Design.
Now, let us discuss two of the essential strategies used in system designing:
- Top-Down Strategy
- Bottom Up Strategy
1. Top-Down Strategy
This strategy breaks down the whole System into subsystems and smaller components and repeats the same process by dividing the subsystems furthermore to form the hierarchy of the system structure. The process continues till you reach the lowest level in the order. The strategy is to consider the whole System as a single entity and keep dividing it by adding the definitions of subsystems.
When one needs to design any software that is required to be developed from the very first stage, the Top-Down approach is the best choice for them.
The benefit of using the Top-Down approach is that it strongly focuses on the System's requirements and helps to make the System design more responsive.
The only problem with this approach is that it neglects the advantages you could get in a simple architecture. Also, it reduces the ability to reuse the same component.
2. Bottom-Up Approach
Unlike the Top-Down approach, in the Bottom-Up process, we build the whole System by adding the components to the lowest level elements and then moving up in the hierarchy. The following immediate higher-level members are created by adding new functions to the current level, and the process is repeated till all the components are embedded.
Hence the Single component at the highest level is considered the whole System.
When you already have some basic information and ants to build a system through it, the Bottom-Up approach is best for such tasks.
The perk of this approach is that one can easily reuse the primary/ general components in this strategy.
The fault in this approach is that it is harder to implement and can sometimes lead to the proliferation of valuable functions in place of appropriate ones.