Essentials of Systems Analysis and Design

Course Name: Essentials of Systems Analysis and Design (1) Course number: 507322 Instructor: Dr. Enas Al-lozi Chapter 1: The Systems Development Environment Summary ? What is the key to success for any organization? The ability to gather, organize and interpret information through systems analysis and design.

? What is systems analysis and design? It is a method of creating and developing information systems that perform basic functions. ? Why the need to develop new Information systems? 1. To solve current problems within the organization. 2. To replace traditional information systems that is not capable of solving current problems. .

To upgrade the efficiency of existing information systems in order to deal with the turbulent environment. ?

What is a system? It is a set of interrelated components that are working together to achieve a certain purpose. ? What are the characteristics of a system? 1. Components: The parts or sub-systems that make a system. 2. Interrelated components (relationships between the sub-systems): every sub-system is dependent on the other.

3. Boundary: the line that separates the system from the outside (external environment). 4. Purpose: all components work together to achieve a purpose (the reason of existing). . Environment: everything external.

6. Interface: point of contact between the system and the external environment. 7. Input. 8.

Output. 9. Constraints: Limitations of what a system can do. ? What do we mean by decomposition? Before developing an information system, you need to understand the components of the system to be developed. It is the process of breaking down the system into sub-components to: 1. Easily manage and understand.

2. Focus on one part at a time. 3. Understand what users exactly need. 4. Build each sub-system one at a time.

? What is modularity?

Modularity refers to the modules (sub-systems) that have been decomposed. It is different from decomposition is that the modules could be systems, each with sub-components. ? What is coupling? Coupling is when a sub-system is dependent on another sub-system, and one alone cannot achieve its purpose. A mobile phone cannot work without sub-components working together. ? What is Cohesion? Cohesion means that each sub-system can perform a single function, like the battery in a mobile phone. ? What are the major roles of a system analyst? 1.

Study the problems. 2. Determine users’ requirements and needs. What are the skills needed to be a system analyst? 1. Analytical skills: analyze the business functions, the problems, and find solutions. 2.

Technical skills: be able to understand and use the information technology. 3. Managerial skills: being able to manage projects, resources, and risks. 4. Interpersonal skills: know how to work with users and other analysts and programmers. ? What are the four stages of developing an information system? 1.

Planning and selection of the system. 2. System analysis. 3. System design.

4. System implementation and operation. ? What do we mean by “planning and selecting” the system?

The first step in developing the system includes planning for the project, defining the problem, choosing the type of system, planning the scope of the project, the feasibility study, and managing the time, money and resources for doing the project. ? What is “system analysis”? System analysis includes determining the requirements of users, analyzing the current systems, and how to replace them or enhance them. ? What is “system design”? The designing phase has two stages; the first stage is the logical design which means creating a model or prototype or drawing a sketch of the system.

The second stage is the physical design, which means turning the sketch or model into a physical one and operating all its hardware and software parts. ? What is “system implementation and operation”? This stage includes coding, testing and implementing the systems software applications to make work; it is usually done by system developers and programmers, then operating the system on users’ computers. ? What are the methodologies, techniques, and tools used to improve system analysis and design? 1. Prototyping. 2. Computer-Aided Software Engineering (CASE).

3. Joint-Application Design (JAD) 4. Rapid Application Design (RAD). 5.

Participatory Design (PD).

6. Agile Methodologies. ? What is “prototyping”? Prototyping means building a first version of the system (a physical simple model). ? What are the advantages of prototyping? 1. Users are involved in the design and building of the model.

2. Requirements and needs of users are clear. ? What are the “CASE” tools? CASE is automated software used by analysts to develop information systems, it helps increase the quality of the system. ? What is “JAD”? A process where users, managers, and analysts work together to determine system requirements, needs, time and resources, and review the design. ? What is “RAD”?

RAD is software that uses the prototype of the model to get users’ acceptance of the model features, interface and make sure the requirements are right. In other words, it delays the process of building the physical system until making sure the details are completed.

? What is “PD”? PD is a process where every user participates in the designing of the system, users of the inside and outside community. ? What is “Agile Methodologies”? They are approaches used to develop an information system that is adaptive to any circumstances by focusing on people and making them develop analytical skills to help design the project. End of Chapter