In: Computer Science
What are the essential elements of the design side of a systems SAD?
Systems development is systematic process which includes phases such as planning, analysis, design, deployment, and maintenance. Here we have to focus on System Analysis and Design(SAD).
Systems Analysis
It is a process of collecting and interpreting facts, identifying the problems, and decomposition of a system into its components. System analysis is conducted for the purpose of studying a system or its parts in order to identify its objectives. It is a problem solving technique that improves the system and ensures that all the components of the system work efficiently to accomplish their purpose. Analysis specifies what the system should do.
Systems Design
It is a process of planning a new business system or replacing an existing system by defining its components or modules to satisfy the specific requirements. Before planning, you need to understand the old system thoroughly and determine how computers can best be used in order to operate efficiently. System Design focuses on how to accomplish the objective of the system.
System Analysis and Design (SAD) mainly focuses on −
Elements of a System
The following diagram shows the elements of a system −

Outputs and Inputs
The main aim of a system is to produce an output which is useful for its user. Inputs are the information that enters into the system for processing. Output is the outcome of processing.
Processor(s)
The processor is the element of a system that involves the actual transformation of input into output. It is the operational component of a system. Processors may modify the input either totally or partially, depending on the output specification. As the output specifications change, so does the processing. In some cases, input is also modified to enable the processor for handling the transformation.
Control
The control element guides the system. It is the decision–making subsystem that controls the pattern of activities governing input, processing, and output. The behavior of a computer System is controlled by the Operating System and software. In order to keep system in balance, what and how much input is needed is determined by Output Specifications.
Feedback
Feedback provides the control in a dynamic system. Positive feedback is routine in nature that encourages the performance of the system. Negative feedback is informational in nature that provides the controller with information for action.
Environment
The environment is the “super system” within which an organization operates.It is the source of external elements that strike on the system.It determines how a system must function.
Boundaries and Interface
A system should be defined by its boundaries. Boundaries are the limits that identify its components, processes, and interrelationship when it interfaces with another system. Each system has boundaries that determine its sphere of influence and control.The knowledge of the boundaries of a given system is crucial in determining the nature of its interface with other systems for successful design.