Applications and Applications and implications of information implications of information and communications and communications technologytechnologySection 4

Use terms associated with Use terms associated with datadatacommunications and communications and networks;networks;Data communications and

network-Data communication is the transfer of data from one device to another via some form of transmission medium.

Types of NetworksTypes of NetworksA Local Area Network (LAN) -is confined to a

relatively small area. It is generally limited to a geographic area, such as a writing lab, school or building.

AdvantageIncreased productivity as network users can work

on a single document simultaneously. Facilitates faster communication via email

DisadvantageInitial set-up cost can be very high. There is an increased risk of data corruption.

Wide Area NetworkWide Area Network

Wide Area Networks (WANs) connect larger geographic areas, such as a city, a country or the world.

Metropolitan Area Network Metropolitan Area Network (MAN(MANConnects LANs in a metropolitan

area and controls data transmission in that

area.

Network LayoutNetwork Layout

This refers to the physical layout of a network, that is, how the computers are connected physically. Network layout is also known as the network topology.

There are three main types of network layouts: star, bus and ring.

Star layoutStar layout

All the nodes are connected to a central

hub

AdvantagesA break in a cable will not affect

other computersFastestDisadvantagesIf the hub fails, the network failsMore expensive to install

Bus layoutBus layout The network nodes are connected in a

line

AdvantagesCheap and reliable

DisadvantagesIf the main cable breaks, network

is split into two unconnected parts

Slower than Star

Ring layoutRing layout There is no end to the connection

because the first node is connected to the

last, forming a ring.

AdvantagesCan span a larger distance than BusTransmission Faster than Bus

DisadvantagesA break in the cable will affect all

computers.Slower than StarDifficult to install

Types of Telecommunications Types of Telecommunications MediaMedia

Twisted pair wire cable Insulated pairs of wires

historically used in telephone service and to connect computer devices e.g. Telephone wires

Coaxial cable Consists of an inner conductor wire surrounded by insulation, called the dielectric. Coaxial cable has better data transmission rate than twisted

pair E.g. tv cable

Types of Telecommunications Types of Telecommunications Media (Media (

Fiber-optic Cable

Many extremely thin strands of glass or plastic bound together in a sheathing which transmits signals with light beams

Can be used for voice, data, and video

Types of Telecommunications Types of Telecommunications MediaMedia

Microwave Communications Line-of-sight devices which must be placed in relatively high locations

Microwave usage Information is converted to a microwave signal, sent through the air to a receiver, and recovered

Types of Telecommunications Types of Telecommunications MediaMedia

Satellite transmission Communications satellites are relay stations that receive signals from one earth station and rebroadcast them to another

They use microwave signals

Types of Telecommunications Types of Telecommunications MediaMedia

Infrared transmission Involves sending signals through the air

via light waves

Requires line-of-sight and short distances (a few hundred yards)

Used to connect various computing devices such as handheld computers

Bandwidth: Refers to the width of the range of frequencies (the amount of data that can be carried form one point to another) that data can travel on a given transmission medium.

Narrow-band - This channel can transmit data at slow speeds of between 10-30 characters per second (30 cps) and is made use of in the telegram system.

Voiceband: Transmits data at a rate of 300 bps to 9600 bps. Cable commonly used is Unshielded Twisted Pair (UTP).

Broadband: Transmits data at a rate of up to 1000s of characters per second. Cables commonly used are coaxial and fibre optic.

Direction of data flowDirection of data flow

Refers to whether data can be transmitted in

only one direction or more. Three types:

Simplex: data travels in one direction only.

Half-duplex: data travels in both directions but only one at a time.

Full duplex: data travels in both directions simultaneously

Wireless NetworkWireless NetworkWi-Fi - Wi-Fi is an abbreviation

for Wireless Fidelity , it enables the user to deploy a computer network without needing to run cable throughout the facility.

Bluetooth Bluetooth Is the standard for wireless

personal area networks or WPAN( Wireless Personal Area Network). It allows high speed transmission of data over very short distances. Bluetooth is normally used for transferring data between laptops

A hotspot is any public area where computers that have been fitted with wireless network technology can gain access to the Internet.

Modem, short for modulator-demodulator is an electronic device that converts a computer’s digital signals into specific frequencies to travel over telephone or cable television lines

Point to point: a direct link between two computers.

Broadcast: using one computer to transmit data and information to serve the needs of several terminals or computers connected to it in a network.

distinguish among Internet, distinguish among Internet, intranet and extranet;intranet and extranet;The Internet -is described as a

network of networks. It consists of over 50 million computers worldwide

Intranet - a type of network belonging to and is used exclusively by a particular company.

Extranet - allows authorised users limited access to an intranet.

ADVANTAGES OF THE INTERNETInformation on virtually any topic can

be found on the Internet.Cultural barriers can be broken.Work from home.E-commerce.Access to professional feedback.DISADVANTAGESCost of equipment may be high.No control on the quality of

information.Possible to download malicious

content.

explain concepts associated explain concepts associated with the Internet; with the Internet;Electronic mail - permits the

transmission of documents from one terminal or computer of another via the Internet.

Advantages of email Messages are sent instantly, thus

increasing retrieval time. It is very convenient. Disadvantages of email We cannot send email to people

who do not have an email account.

Bulletin board - similar to the normal bulletin board, it is a centralised computerised location, to which remote computers can connect. Once connected, a user may upload a file or download those posted by others.

News group - this may be one of several online discussion groups covering a particular subject or interest.

Internet Relay Chat (IRC) - this feature allows two or more persons from anywhere in the world to participate in live discussions. Instant messaging programmes include ICQ, MSN messenger and Yahoo messenger.

Telnet - this is one of the ways that a person can access a remote computer over a network such as the Internet. It is often used by individuals or companies that seek to limit the privileges of people who are logging onto their computer(s) via telnet.

World Wide Web (www) - one of the components of the Internet consisting of a collection of text and media documents called web pages.

Web pages - a group of one or more related electronic documents. Web pages are usually encoded in a special language called Hypertext Mark-up Language (HTML) that allows one web page to provide links to several others.

Website - a group of related web pages on the same server.

Web browsers - special software that allows users to view web pages, for example Netscape and Internet Explorer.

Search Engine - the name given to a software or website that allows a user to find information quickly by typing in keywords or phrases.

Hypertext Transfer Protocol (HTTP) - governs the transmission of web pages over the Internet.

File Transfer Protocol (FTP) - the set of rules used to govern the sending and receiving of files on the Internet.

Uniform Resource Locator (URL) - a unique address attached to each web page or Internet file. For example www. informationtechnology.com

Down-load Process whereby programs or data are transferred via communications

channels, from a computer and stored on media located at the user’s

computer.

Blog -A blog is an online journal or diary of an individual’s opinions and latest news.

Podcasting -A form of audio broadcasting using the Internet;

VoIP Acronym for Voice over Internet Protocol. -It is a protocol which governs the transmission of voice over the Internet.

Web Server -A computer that delivers (serves up) Web pages.

Upload-To transmit data from a computer to a bulletin board service, mainframe, or network.

E-Commerce or Electronic Commerce-business that is conducted over the Internet

Electronic Learning or -e-learning- is essentially the network-enabled transfer of skills and knowledge

Describe measures to Describe measures to secure data and maintain secure data and maintain data integrity;data integrity;Software RestrictionsSoftware Restrictions

Password - A sequence of characters required for access to a computer system.

Encryption and Encryption,- is

where data are encoded before transmission and decoded afterwards

Cont’dCont’dVirus protectionThis can be used to protect a

computer from and intercept harmful viruses attempting to infect a system, as well as scan for same.

Firewall- is used to stop computers on other networks, including the internet, accessing an intranet.

Physical Access Physical Access RestrictionsRestrictions

Biometric system- These systems use some part of a person’s body to uniquely identify them.

Guards- Security guards should be properly instructed about their duties. The employees who access secured areas should have proper identification and authorization to enter the area.

Fireproof cabinets and disc locking

The user may use fireproof cabinets and safes to store CDs, DVDs and other devices.

Discs can be locked by covering the write-protection hole. This prevents the changing, deletion or infection of files contained on these devices.

Backups and archivesThis includes making regular and recent copies of files and storing them on an external storage device. By doing this, a user will always have a recent copy of

his data, regardless of what happens to the original.

Proprietary data is an internally generated software that contains technical or other types of information controlled by a firm to safeguard its competitive edge.

Propriety software is computer software which is the legal property of one party.Eg. of proprietary software are Microsoft Windows, Real Player and I-tunes.

outline ways by which outline ways by which information can be misused;information can be misused;Propaganda: This is the use of

computer systems, more specifically the Internet, to distribute harmful information that may be used to tarnish the image of an individual.

Identity theft is the deliberate assumption of another person’s or an organization’s identity, usually to gain access to financial information.

Computer Fraud-refers to when an individual gains access to a financial account and changes the details of this account to the owner's detriment and to the individual's advantage.

Industrial espionage-This is when an organisation tries to gain an advantage over competitors by illicitly gaining access to information about that competitor's strategies.

Electronic eavesdropping -refers to the use of electronic devices to monitor electronic communications between two or more communicating parties without permission from any of those involved.

Credit card fraud- is the act of making a purchase using someone else's credit card information

Surveillance-This refers to the use of computers and related technology to observe something or someone with close scrutiny without permission

Software piracy -is the unauthorised copying or distribution of copyrighted software. This can be done by copying, downloading, sharing, selling, or installing unlicensed copies onto personal or work computers.

Storage of Inaccurate Information- is

data collected that have been incorrect or

misleading.

Violation of Privacy: mishandling private information, such as customer passwords or social security numbers.

describe appropriate hardware and software to meet describe appropriate hardware and software to meet

the particular needs of a given applicationthe particular needs of a given application;; Banking Some of the functions of computers in banking

include: Processing transactions of customers (e.g. deposits and

withdrawals, loans) Electronic fund transfer (the transfer of money using

electronic methods)

Some of the hardware used in banking are: Line printers that are used for printing reports and

customer statements Character printers which print transactions in bankbooks Automated Teller Machines (ATM)

Some of the software used in banking are: Word-processing software used for preparing

correspondence Wide Area Network (WAN) software.

Education-In education, information systems can be seen in the classrooms with computer- aided instruction and also for administrative purposes in keeping students' records.

Computers also support learning in the following ways:

1.Research purposes (Internet or encyclopaedia CD ROMs are used.

2.Computer Assisted/Aided Learning (CAL)

Cont’dCont’dSome hardware used in

education are: PCs Voice synthesis for teaching people

with speech and hearing disability Laser and inkjet printers. Some of the software used in

education are: Word processors - to prepare

lesson plans, letters, tests or assignments

Spreadsheet

Engineering and design -the advent of computers, this task, in addition to those previously listed is done using the computer primarily using software such as:

Computer Aided Design (CAD) - for drawing 3D technical drawings.

Computer Aided Design and Drafting (CADD) - for both 2D and 3D drawings

Some of the hardware accompanying the Computer Aided Design and engineering software are:

PC connected to a minicomputer or mainframe computer

High resolution monitors Flatbed or drum graphics plotter Inkjet or laser printers

Science and technology- Information systems are used in weather forecasting,

medical research and virtual-reality simulations.

Commerce-In commerce, computers are used in researching the sales potential of new products and to automate the communication between customers and a company. They are also used in checking stock levels and reordering when necessary.

Manufacturing-In manufacturing, computers are used to automate processes such as a

car-assembly line. These computers are

sometimes called robots.

Law enforcement-Computer systems are used in law enforcement to keep databases of felons and fingerprints of same. They are also used in forensic computing, where samples of chemicals can be compared, as well as voices and call logs

Recreation and entertainment-In this, computers are used to edit music, photos and videos. They are also used to watch

movies and for high-performance game playing.

Information in organisations-Information as a commodity simply means that it can be bought or sold.

Describe current and emergingDescribe current and emergingtechnological trends;technological trends;

Expert systems: computers are programmed

to make decisions.

Robotics: computers are programmed to respond to sensory stimuli.

CADD: Computer Assisted design and Drafting software is used to aid in the design and drafting of a product. It is used to create two- and three-dimensional engineering and architectural drawings.

CAM: Computer Assisted/Aided Manufacturing software assists engineers and machinists in manufacturing or prototyping product components. It is a programming tool that makes it possible to manufacture physical models of a product.

CAE: Computer Assisted Engineering is used in the different fields of engineering. It involves data collection, analysis, manipulation, reporting and communication. The form in which the data come varies with the field of engineering.

Teleconferencing-enables video and voice transmission over long distances and can be done between branches and continents.

Telemarketing-refers to individuals calling potential customers to market goods and services. In telemarketing, the phone calls are sometimes made by computers.

Telecommuting -refers to employees working from home saving on transportation costs.

Assess the impact of InformationAssess the impact of InformationTechnology on job skills and Technology on job skills and careerscareersSkills used by Office employees

Word processing and document preparation

Communication- via fax, email etc

Basic trouble shooting of hardware and software

Skills used by teachersWord processing, spreadsheet

manipulationPreparing presentationsInstallation and basic

troubleshooting of hardware and software

Database management-creating and searching databases.

Skill used by engineersInstallation of hardware and softwareUsing communications system

(LAN,WAN)Software programming- the ability to

design, test and implement new software

Skills of a Medical PersonnelPrepare budgets medical bills,

insurance Word processing and document

processingManipulate hardware, patient

monitoring, and imaging such as MRI and CAT scan technology

Skills of a MusicianUsing MIDI hardware to produce

music and interfacing with computer systems to add instruments, sound, special effect etc.

Using music notation software for composing music and preparing lyrics.

Skills of a Mass media personnel

Word processing-preparing articles, news scripts

Communications using email, fax, forums

Using hardware and software for films and sound editing before going to the final press.

Skills of Law enforcement personnel

Word processing and document preparation-used in case reports, letters

Database searches-accessing records dept on know offenders.

Skills of Movie Industry Personnel

Word processing and document preparation-used for preparing movie scripts

AnimationsAccounting and budgeting

software can be used to crate cost and income estimates for movies

describe the roles of various describe the roles of various personnel in computer-related personnel in computer-related professions.professions.

Data processing managerResponsible for planning, coordinating,

managing and staffing of the data processing department of a large organisation.

Database administratorResponsible for the administration and management of a company's database. This involves the effective and efficient storage, retrieval, customization and archiving of data

ProgrammersThese can be classified into

applications programmers (write software to meet user requirements) and system programmers (write software for the system such as ones that monitors and controls peripheral devices). Duties include writing, testing, debugging programmes and updating and modifying existing ones.

System analyst-Looks at the operations of a

manual or computerised system in an organisation and tries to find solutions to

end user problems by implementing a new computerised system or upgrading an

existing one.

Network administrator-Responsible for the

creation, administration, and security of a company's network.

Computer consultantProvides technical assistance and advice to an organization in the formation or upgrading of a data-processing department.

Data control clerkScreens, edits and validates the input and

output for a data-processing unit. Duties include regulating workflow in accordance with

operating schedules, being in charge of the receipt, safekeeping and retrieval of data, hardware, software and security items.

Data entry operator-Enters data into a system in a form that is suitable for processing. Duties include: keeping records on the data transcribed and verifying the data entered.

Computer engineer-Found at all levels of the computer industry, they design components for use in or with a computer. Responsible for the maintaining and

repairingof computer hardware sold to clients.

Librarians-manages data files and programs

stored off-line on tapes disks and microfilm etc.

Software package Writer- These are programmers who create software

commissioned by individual customers designed for sale to large numbers of users.

Software Tester- Checks to ensure that the

application developed works the way it was intended to, and that it is up to standard

and quality expected.

Webmaster- responsible for maintaining an existing website by editing or updating text, graphics and links to update the content

Web designer- mainly responsible for the

visual appeal of the website.

Web Developer- Builds websites, which involves writing the programming code necessary for an efficient and stable website.

Computer Trainer- sets up training sessions to provide education about particular computer program, system or technology