AT1033 Lecture3 -Networking

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ICT FOR SOCIAL SCIENCES TYPE OF INFORMATION AND NETWORKING IN ICT

Transcript of AT1033 Lecture3 -Networking

ICT FOR SOCIAL SCIENCES

TYPE OF INFORMATION AND NETWORKING IN ICT

Introduction

A computer is part of an information system

Hardware Software Data People Procedures Telecommunications

The components of a computer-based information system:

Telecommunications It is the electronic transmission of signals.

Networks are collections of hardware connected together for telecommunications.

People Those who use the information provided by the hardware and software. (end-users)

Those who supply the raw data for processing

Those who write programs (programmers) Those who support the running of the system (computing officers, support engineers).

Procedures

The rules or guidelines for the running of the information system and its components.

System manuals Program manuals

Data and Information What is data?

Data is unorganised facts, numbers, letters and symbols represented in a formalised manner suitable for communication, interpretation and processing by humans or computers.

What is information? Information is data which has been assigned a commonly understood meaning.

AB34652 22025 46723 45890 98345

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Data

Information

Number of Products Sold in November in All Sales Areas

Product South North East West

AB34652 22025 46723 45890 98345

• Daily work• Study• Management• Administration• Military/Security• Business• Decision Making

THE NEEDS FOR INFORMATION

• How to obtainVariety of source – books, newspaper,radio, tv

• How to storeVariety of forms – text, picturesymbol

• How to passVariety of forms – writings, voiceimage (Audio,Video)

FACTS ABOUT INFORMATION

• Accurate• Fast and easy to obtain• Complete• Simple• Related• Quality• Trustable• Update

CHARACTERISTIC OF INFORMATION

What is a System?

A system is an organised set of related components established to perform a certain task.

Information System

A set of components that work together to manage the acquisition, storage, manipulation, and distribution of information.

Input

Processing

Output

Storage

Components of a Computing System

Central processingunit (CPU) holds

instructionstemporarily anddata and programsexecutes computer

Input devicesends data tothe centralprocessing unit

Output devicemakesprocessed

(information)available

data

Secondary storagedevice stores dataand programs

Four Hardware Components

An information system has three basic function:1. to accept data (input)2. to convert data to information (process)3. to produce and communicate information in a timely fashion to users for decision making (output).

DATA PROCESSING INFORMATION

INPUT OUTPUTSimple system process

Information System Process

1. Data inputi)

Recording data into a data-processing medium (e.g.,key-

in numbers into MS Excel). ii)

Coding data into a different, easier to use mode (e.g.

converting the gender attribute “female” to the letter F).iii) Storing data or information.iv) Selecting from among multiple data items for decision

making. 

Information System Process

2. Data transformationa) Calculating new amounts using arithmetic operation on the

datab) Summarizing by accumulating several data items

(e.g., adding hours worked for each day of the week into a

single total of hours worked per week)c) Classifying data into separate, identifiable groups

3. Information outputa) Displaying results of data modification for information users

(e.g., producing payment totals on a printed report).b) Reproducing (copying) stored data for use by multiple

users.c) Telecommunicating stored data electronically over

communication media (e.g. SMS, email).

Information System Process

Types of Data in Social ScienceThe types of ICT data can be categorized as follows but the format is based on the softwares.

Spreadsheet (MS Excel, SPSS) Database (MS Access, Oracle, Sybase)

Graphic (Chart or Graph) GIS (ArcGIS, Mapinfo) MultiMedia (video, sound, picture)

Communications Communications, refers to the ability to exchange data over a distance—over local connections, long-distance phone lines, via privately owned cable, or by satellite.

Communications has greatly expanded the usefulness of the computer in the workplace and been one of the main causes for the increasingly widespread use of the computer in the home.

INFORMATION NETWORKS

Advantages of Networking Sharing Hardware

printers in the labs file-store F on a campus network server

Sharing Files pokeman.txt, wordprocessing.txt

Sharing documents E-mail Eudora

Exchanging Data workgroup computing

Computer NetworksTwo or more computers connected together to exchange data and share facilities

Local Area Network (LAN) a network that connects computers a network that connects computers located within a limited geographic arealocated within a limited geographic area

Wide Area Network (WAN) a network that connects computers over a a network that connects computers over a wide geographical area, other across wide geographical area, other across international boundaries.international boundaries.

The Telephone Network Public Switched Data Network (PSDN)

Public Switched Telephone Network (PSTN) analogue speed measured in bauds (bits per second) band rate 56Kb at present

Integrated Service Digital Network (ISDN) digital 64Kb and 128Kb at present

Fax (facsimile) sending scanned copies of documents

Telex sending and receiving messages via a electric typewriter

ModemStands for modulator/demodulator. Performs the function of converting digital signals into analogue signals and vice versa.

Internal modemInterface circuits on a plug-in card with a standard plug that the telephone jack can fit into.

Modems

The Internet A world-wide network of interconnected computers and computer networks

Electronic mail (e-mail) Hotmail, Netscape Mail, Yahoo MailHotmail, Netscape Mail, Yahoo Mail

World Wide Web BrowserBrowser

Netscape Navigator, Internet Explorer, MozillaNetscape Navigator, Internet Explorer, Mozilla Search EngineSearch Engine

AltaVista, Lycos, Excite, Yahoo, GoogleAltaVista, Lycos, Excite, Yahoo, Google Internet Service Provider (ISP)

Your access to the InternetYour access to the Internet

Internet TerminologyDomain Type Comment.com Commercial User.net Network Provider.edu Educational

Institution.org Non-profit

organizational.gov Government.mil Military.my / .jp / .au / .us

Country name (Malaysia, Japan, Australia, United States)

HTML Hypertext Markup Language (HTML) is a system of marking up or tagging a document so it can be published in the internet.

Each web page must include HTML file in which have extension of (.html)

The source code for HTML can be view and modify using any web developer software.

Web Page in InternetThere are three types of Web page: i. Static Web documentsii. Simple, interactive Web pageiii.Complex Web-based database

systems

Web developer softwareThe web page in Internet can be developed using software such as;

Microsoft Frontpage 2000 Macromedia Dreamweaver Word processing software (MS Word, Notepad)

Disadvantages of using InternetThe four most important barriers to Internet use were:

speed lack of security legal/confidentiality issues costs