Structured Analysis and Design
Structured system analysis and design method
A Structured Method helps software developers to cope with large and complex
software. This method defines structured steps in software development process,
starting from planning, analysis, design, implementation, and supporting.
step defines and clarifies user and system
requirements. During structured analysis, ERD and DFD are produced.
(Entity-Relationship Diagram) is presented to define
and clarify entities, attributes, and their
relationships, and constraints applied to them. DFD
Diagram) depicts the system components—processes, external entities that
interact with the system, and information flow in the system.
After you understand the problem clearly, it is the time to solve it.
defines a solution to the problem. Structured design
tasks are performed to translate what produced in system analysis to blueprint
of the system that can be implemented. During structured design, the four design
models are presented.
transforms ERD in to data structures required to
implement the software.
Entities, attributes, and relationships are the basic for design activities.
define a higher-level structure of the
system. The higher-level structure of the system depicts the relationship
between the structural components or modules of the system. Structure Chart is a
good visual presentation of Architectural design.
defines interaction of people with the
system, and the system with other systems that work with it . It provides the
best way for people and other systems to interact with the system. Data Flow
Model can be a good input for interface design.
transforms the structural components or
modules of the system architecture in to procedural description of the
components. Pseudo-code or Flow Chart
is a good tool to do the procedural
When program modules are designed, coding
programming use standard control structures to improve clarity, and maintenance.
Structured programming encourages top-down development. A top-level function is
expanded down in to more detail components. Structured programming use SEQUENCE,
IF ELSE, and LOOP to facilitate top-down development. Structured programming
languages initially used are ALGOL, Pascal, PL/I, and Ada. C is the most popular
structured programming language today.