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INFORMATION SYSTEM ANALYSIS & DESIGNINFORMATION SYSTEM ANALYSIS & DESIGN

1) WHAT DO YOU MEAN BY INFORMATION ?2) WHAT ABOUT SYSTEM?

3) WHAT IS INFORMATION SYSTEM?

4) WHAT IS ANALYSIS?

5)WHAT IS DESIGN?

6)WHAT IS SYSTEM ANALYSIS?

7) WHAT IS SYSTEM DESIGN

Overview of today's Lesson (Lecture-2)

1) Study of System concept.

4) Elements of a System

5) Characteristics of a System

6) Boundaries and Interface

System

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WHAT IS INFORMATION ?

• What do you mean by DATA?Data are raw facts about the

organization and its business transactions. Most data items have little meaning and use by themselves.

Information is data that has been refined and organized by processing and purposeful intelligence. The latter, purposeful intelligence, is crucial to the definition-People provide the purpose and the intelligence that produces true information.

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Figure 2.1:- To understand Data and Information

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WHAT IS SYSTEM ?

System is an orderly grouping of interdependent components linked together according to a plan to achieve a specific objective.

Figure-1.2:-A general depiction of a system

Figure:-A general model of a System

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WHAT IS INFORMATION SYSTEM ?

Information System (IS) is an arrangement of people, data, processes, information presentation, and information technology that interact to support and improve day-to-day operations in a business as well as support the problem-solving and decision-making needs of management and users.

Information technology (IT) is a contemporary term that describes the combination of computer technology (hardware and software) with telecom munications technology (data, image, and voice networks).

The term information worker was coined to describe those people whose jobs involve the creation, collection, processing, distribution, and use of information.

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SYSTEM ANALYSIS ?Systems analysis is the study of a business problem domain to recommend improvements and specify the business requirements for the solution.

Systems design is the specification or construction of a technical, computer based solution for the business requirements identified in a systems analysis. (Note: Increasingly, the design takes the form of a working prototype.)

SYSTEM DESIGN ?

WHAT ABOUT SYSTEM DESIGNER ?System designers are the technology specialists for information system

System designers translate system users' business requirements and constraints into technical solutions. They design the computer files, databases, inputs, outputs, screens, networks, and programs that will meet the system users' requirements.

Today's system designers tend to focus on technical specialties such as databases, networks, user interfaces, or software.

Some of you may be educating yourselves to specialize in one. of these technical specialties.

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AND SYSTEM ANALYST !!!

A systems analyst facilitates the development of information systems and computer applications

In this capacity, and as illustrated a Figure in next slide , the systems analyst must interact with each of the other stakeholders in the system. For the system owners and users, the analyst typically identifies and validates their business problems and needs. For the system designers and builders, the analyst ensures that the technical solution ful fills the business needs and then integrates the technical solution into the business. As part of the facilitation, the systems analyst performs systems analysis and design.

We can say also that a System analyst studies the problems and needs of an organization to determine how people , data, processes, communications ,and information technology can best accomplish improvements for the business.

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Study of System concept.

The study of System concepts, then, has three basic implication.

1) A system must be designed to achieve a predetermined objective.

2) Interrelationships and interdependence must exit among the components

3)The objectives of the organization as a whole have a higher priority then the objectives of its subsystems.

For example computerizing personnel applications must conform to the organization’s policy on privacy, confidentiality, and security, as well as making selected data (e.g., payroll) available to the accounting division on request

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Fig-2.1:- System Concepts.

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ELEMENTS OF A SYSTEMIn most cases, systems analysts operate in a dynamic environment where change is a way of life. The environment may be a business firm, a business application, or a computer system. To reconstruct a system, the following key elements must be considered:

1) OUTPUT and INPUT.

2) PROCESSOR(S)

3) CONTROL

4) FEEDBACK.

5)ENVIRONMENT.

6) BOUNDARIES and INTERFACES

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BOUNDARIES AND INTERFACE

Every system has a boundary within which it lies and outside of which its environment. The environment of a business system includes any human, business or political activity that impinges upon the business operation. The environment of an information system is any activity , person or object that gives rise to data or responds to information from the system.

The concept of boundary of a system makes it possible to focus on a particular system within a hierarchy of a systems. The boundary of a system may exit either physically or conceptually. The operational definition of a system in terms of its boundary is :-

1) List all components that are to make up the system and circumscribe them. Everything within the circumscribed space is called the system, and everything outside is called the environment.

2) List all flows across the boundary. Flows from the environment into the system are inputs; flows from inside the boundary to outside are called outputs.

3) Identify all elements that contribute to the specific goals of the system and include these within the boundary if they are not already included.

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CHARACTERISTICS OF A SYSTEMOur definition of a system suggests some characteristics that are present in all system.

Which is as follows:-

1)A system is a whole2) Components of a system

interact.3) Systems are goal seeking.4) System have input/output.

5) Systems transform inputs to yield output. 6)Systems exhibit entropy,7) Systems must be controlled.8) Systems form a hierarchy.

9) Systems exhibit differentiation.10. Systems exhibit

equafinality.