Renu Singh
10-28-2003, 02:00 PM
System Analysis: Structured Approach
The traditional approach of the system life cycle provides very little quality control to ensure accurate communication from user to analyst. To deliver the systems in line with the user’s requirements, the analyst collects a great deal of relatively unstructured data through interviews, questionnaires, on-site observations, procedures manuals and other methods etc. The analyst is quickly overwhelmed with the business and technical details of the system and much of time is spent in gathering information. The details are needed and must be available but the analyst does not have the tools to support and control the details. The traditional approach is to organize and converts the data through system flowchart, which support future development of the system and simplify communication with the users. But the system flowchart represents a physical rather than a logical system, makes it difficult to distinguish between “what happens” and “how it happened” in the system. The approach typically suffered from the following major draws backs in the analytical limitation and structured specifications.
_ English narrative descriptions of a system are often too vague and abstruse for the users to grasp how the parts fit together especially where precision is needed.
_ System and program flowchart commit to a physical implementation of the system before understanding of logical requirements.
_ System specifications are difficult to maintain or modify.
_ They are monolithic and redundant.
_ They describe user requirement in the term of physical hardware that will implement the system rather than what the user want the system to do.
While all these problems were being debated, a complementary set of ideas was already being adopted in the area of programming and design. The analyst needs something analogous to the architect’s blueprint as a starting point for system design. To focus on function rather than physical implementation, Structured Analysis and Design gradually became popular. A new approach involved object-oriented programming (OOP) and object-oriented design (OOD) has generally proved successful.
Structured Analysis is a set of techniques and graphical tools that allow analyst to develops a new kind of system specifications focus on new goals and tools for analysis (DFD, Data Dictionary, Structured English, Decision Tree and Decision Tables etc). Structured Analysis in contrast to traditional approach uses graphic and builds a logical system to accentuate system characteristics and interrelationships before implementation. It has following attributes:
_ A graphical approach
_ Partitioned process: the partitioned process gives a clear idea about the progression from general to specific in the system flow.
_ Logical analysis: System elements do not depends on vendor or hardware. Structured approach specify in precise, concise and highly readable manner the system working and interrelationships
_ Rigorous study: It need a rigorous study of the user area, a commitment that is often taken lightly sometime in traditional approach.
_ Flexibility: Certain tasks that are normally carried out late in the system development life cycle are moved to the analysis phase. Example: User procedures are documented during analysis rather than later in implementation.
In this complex techno-revolution, organizations are using structured analysis techniques to build real-time systems. And to make structure analysis more viable alternative in system development, new notations and new modeling tools added to overcome lacking of classical approached of structured analysis. Example: state-transition diagrams to permit modeling of real-time systems; entity-relationship diagrams to permit modeling of systems with complex data relationships; control flows and control processes etc. The major contribution of structured analysis to the system development life cycle is producing a definable and measurable document---the structured specification, increased user involvement, improved communication between user and designer, reduction of total personnel time and fewer
“Kinks” during detailed design and implementation. Nowadays, system analysis and design involves complex functions, complex data relationships and complex real-time characteristics .Needless to say, the structured analysis approach in the system development life cycle viable alternative to classical and traditional approach, to keep your organization at the “leading edge” of technology.
The traditional approach of the system life cycle provides very little quality control to ensure accurate communication from user to analyst. To deliver the systems in line with the user’s requirements, the analyst collects a great deal of relatively unstructured data through interviews, questionnaires, on-site observations, procedures manuals and other methods etc. The analyst is quickly overwhelmed with the business and technical details of the system and much of time is spent in gathering information. The details are needed and must be available but the analyst does not have the tools to support and control the details. The traditional approach is to organize and converts the data through system flowchart, which support future development of the system and simplify communication with the users. But the system flowchart represents a physical rather than a logical system, makes it difficult to distinguish between “what happens” and “how it happened” in the system. The approach typically suffered from the following major draws backs in the analytical limitation and structured specifications.
_ English narrative descriptions of a system are often too vague and abstruse for the users to grasp how the parts fit together especially where precision is needed.
_ System and program flowchart commit to a physical implementation of the system before understanding of logical requirements.
_ System specifications are difficult to maintain or modify.
_ They are monolithic and redundant.
_ They describe user requirement in the term of physical hardware that will implement the system rather than what the user want the system to do.
While all these problems were being debated, a complementary set of ideas was already being adopted in the area of programming and design. The analyst needs something analogous to the architect’s blueprint as a starting point for system design. To focus on function rather than physical implementation, Structured Analysis and Design gradually became popular. A new approach involved object-oriented programming (OOP) and object-oriented design (OOD) has generally proved successful.
Structured Analysis is a set of techniques and graphical tools that allow analyst to develops a new kind of system specifications focus on new goals and tools for analysis (DFD, Data Dictionary, Structured English, Decision Tree and Decision Tables etc). Structured Analysis in contrast to traditional approach uses graphic and builds a logical system to accentuate system characteristics and interrelationships before implementation. It has following attributes:
_ A graphical approach
_ Partitioned process: the partitioned process gives a clear idea about the progression from general to specific in the system flow.
_ Logical analysis: System elements do not depends on vendor or hardware. Structured approach specify in precise, concise and highly readable manner the system working and interrelationships
_ Rigorous study: It need a rigorous study of the user area, a commitment that is often taken lightly sometime in traditional approach.
_ Flexibility: Certain tasks that are normally carried out late in the system development life cycle are moved to the analysis phase. Example: User procedures are documented during analysis rather than later in implementation.
In this complex techno-revolution, organizations are using structured analysis techniques to build real-time systems. And to make structure analysis more viable alternative in system development, new notations and new modeling tools added to overcome lacking of classical approached of structured analysis. Example: state-transition diagrams to permit modeling of real-time systems; entity-relationship diagrams to permit modeling of systems with complex data relationships; control flows and control processes etc. The major contribution of structured analysis to the system development life cycle is producing a definable and measurable document---the structured specification, increased user involvement, improved communication between user and designer, reduction of total personnel time and fewer
“Kinks” during detailed design and implementation. Nowadays, system analysis and design involves complex functions, complex data relationships and complex real-time characteristics .Needless to say, the structured analysis approach in the system development life cycle viable alternative to classical and traditional approach, to keep your organization at the “leading edge” of technology.