What is meant by information system?

An Information System (IS) is the combination of hardware, communication network, people, software, and data resources that collects, manipulates, and disseminates information to provide feedback to address the objective. For organizations and businesses, the information system is a vital component.

Components of information systems

Hardware

The hardware component of an information system comprises the physical elements of the system. The input and output devices are an important part of technology that allows humans to interact with computers and information systems. Input devices include keyboards, microphones, scanners, and mice. The output devices include monitors, speakers, printers, and video cards. The hardware like hard drives, microprocessors, removable storage, and electric power supply allows the computers to store and process data.

Software

Software is an intangible program that manages information systems functions like input, processing, storage, and output. Software in computers is classified into two kinds namely applications software and systems software.

Application software: These are programs that have direct assistance from the end-users. It is a ready-to-use package, which can be purchased.

System software: The programming is simplified using system software. It is easy to manage system resources. The operating system is the principal software system and manages the computer system. System software provides an interface where the system users can deploy all the resources.

Databases

The database is a collection of organized interrelated data, which is used by the application software. System software will manage certain databases and those databases are known as Database Management System (DBMS), which shares multiple applications. The database allows the user to perform fundamental operations like retrieval and storage.

Telecommunications

The telecommunication network allows the computers and storage services to access the information from the cloud. The electronic transmission of data over a distance is known as telecommunication. It can process several network configurations like Local Area Network (LAN), Wide Area Network (WAN), and Metropolitan Area Network(MAN).

Generally, network information systems have three-tier architecture. The top-level with mainframe computers, a middle level with minicomputers and microcomputers, and the third tier consists of end-users.

Human resources

The crucial part of the information system is human resources. End-users are the ones who use the information systems. The human component of information systems development comprises qualified people who can influence and manipulate software, data, and processes. An information system personnel includes system analysts, development managers, programmers, operators, and maintenance managers with specialized skills. The humans involved in the information systems are information security analysts, system analysts, and business analysts.

Methods for acquiring information systems

External acquisition

The steps involved in external acquisition are as follows:

• System planning.
• System selection.
• System analysis.
• Development of proposal request.
• Proposal Evaluation.
• Vendor selection.

Here, the system planning, selection, and analysis are the same as Software Development Life Cycle (SDLC). The competitive bid process helps in finding the best system with the lowest price. During the development of the proposal request, the summary of the existing application and system, system features and performance, evaluation criteria, budget, and service requirement is provided. In the proposal evaluation step, an assessment of the proposal is received from the vendor and a standardized test is conducted to compare different proposals. It includes both system benchmarking and system demonstration. In last step (vendor selection) it determines the best fit as multiple systems will meet the given criteria and also prioritize the proposed system.

Outsourcing systems development

Outsourcing systems development is used to turn over the responsibility of all or some of the organization’s information system operations to an outside firm. The application can run on their computers and solutions can be housed in the outside firm. An outside firm can develop a system to run on the existing computers. Outsourcing is needed for the following reasons,

• Supplier pressure.
• Quality and cost concerns.
• Problems in performance of information system.
• Internal irritants.
• Financial factors.

Techniques used in acquiring information systems

Traditional system lifecycle

The software development life cycle (SDLC) is one of the traditional methods to acquire information systems. It needs to complete six sequential stages to build the system. The six stages are,

• System investigation
• System analysis.
• System design.
• Programming and testing.
• Implementation.
• Operation and maintenance.

SDLC is used to develop medium to large mainframe-based systems. SDLC is structured and builds a system by completing the six stages. The main advantage is error detection, accountability, and ease to control. The disadvantages like relatively inflexible, expensive, and time-consuming.

Prototyping

Prototyping is a method to build an experimental system faster and at a low cost. Prototyping is used when there is an unclear or improper user requirement. The organization needs to analyze the need and justify in terms of benefits and cost. The cost-benefit analysis is done using return on investment, net present value, and breakeven analysis. The advantage is it is faster and has user involvement. The disadvantage is quality of the system is poor and lacks standards.

Software package

The process of purchasing the programs which are readily available (written and tested) is known as a software package. It is used at common system solutions. Before purchasing it needs to check for the application run and cost. The advantages are technical skills are limited, save the cost, and clear the expectations. The disadvantage is not all the requirements are addressed.

End-user development

The process of building a system by the end-users with no formal technical assistance is known as end-user development. This is used for personal and small applications. The alternative methods for development are agile development, end-user development, and rapid application development. The advantage is there will be no misunderstanding in systems development. The disadvantages are control loss and scope are limited.

Outsourcing

An external vendor is used to operate or develop an organization’s information system. The steps are used for selecting the software are identifying a potential vendor, determination of evaluation criteria, package and vendor evaluation, selecting the package and vendor, establishing the service level argument. The advantages of outsourcing are low cost and easy to predict. The disadvantages are loss of control and quite risky.

Context and Applications

This topic is important for postgraduate and undergraduate courses, particularly for, 

• Bachelors in Computer Science Engineering.
• Associate of Science in Computer Science.

Practice problems

Question 1: Softwares in computers are classified into _____________ and ______________.

a) System design and infrastructure design

b) Application software and system software

c) Vital component and software component

d) None of the above

Answer: Option b is correct.

Explanation: Software is one of the components of an information system. The computer software is classified into application and system software.

Question 2: Select the approach which is used in acquiring information systems.

a) Traditional system life cycle

b) System design

c) Infrastructure

d) Systems development

Answer: Option a is correct.

Explanation: One of the traditional methods to acquire information systems is the traditional system life cycle. Six sequential steps need to be followed to build a system. This method is simple to detect error and easy to control.

Question 3: How many steps are involved in external acquisition?

a) 8

b) 4

c) 6

d) 3

Answer: Option c is correct.

Explanation: Acquiring information systems illustrates how the organization can acquire systems using external acquisition, application service provider, and outsourcing. The external acquisition has six steps and they are system planning, selection, analysis, development of proposal request, proposal evaluation, and vendor selection.

Question 4: Network information system has ____ tire architecture.

a) 3

b) 2

c) 5

d) 4

Answer: Option a is correct.

Explanation: Network information systems have three-tier architecture. The top-level with mainframe computers, a middle level with minicomputers and microcomputers, and the third tier with end-users.

Question 5: ___ methods are used in acquiring an information system.

a) SDLC

b) System design

c) Systems development

d) None of the above

Answer: Option a is correct.

Explanation: SDLC is one of the traditional methods to acquire information systems. SDLC needs to complete six steps to a build a system and the steps are system investigation, system analysis, system design, programming and testing, implementation, operation, and maintenance.