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    A2 Revision

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    Section 5

    Expert systems

    Monitoring and measurement

    Project management

    Modelling

    Market research

    Research applications Online applications

    Stock control

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    Expert systems

    Use reasoning (knowledge), set of rules, solve problem by series of

    questions,only used where human knowledge exists, uses expertknowledge, rules base and inference engine, user interface.

    Applications mineral prospecting, investment analysis, financial planning,car engine diagnosis, medical diagnosis, route delivery scheduling, plant &

    animal identification.

    ADVANTAGES

    Reduces time, accuracy, allows experts to do more important things, savesmoney on experts salaries, training, etc.

    DISADVANTAGES

    Expensive set up costs, training required, constant updating, required inevery dept.

    http://www.teach-ict.com/as_a2_ict_new/ocr/A2_G063/334_applications_ict/expert_systems/miniweb/index.htm

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    Monitoring andmeasurement

    The use of computer or microprocessor-based device to monitor or measurephysical variables.

    Uses sensors, which measure things such as temperature, humidity,pressure An ADC then sends information to microprocessor and then to a

    computer.

    Results are shown on a graph, printed or even putput through speakers.

    The software used is normally called a data logging system.

    Examples include: Medical applications, Weather monitoring, climate monitoring,scientific experiments

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    Project management

    Ensure that a project completes on time and not above the budget allowedby the company.

    Gantt charts, Pert charts and event chain diagrams and special softwareare used to enable the division of tasks which can be done at the same timein order to save time and/or money.

    There are 2 types:

    Software development:

    When a new piece of software which has to be produced to solve a particularproblem is broken down into modules. The steps normally are: writing the code,testing and implementing.

    Some modules will be written in sequence, while others will be done at the same

    time.

    Building construction:

    When a new piece of construction has to be built and ICT is used to decide whatparts can be done first and which can be done later.

    Its possible to have certain tasks run at the same time.

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    Modelling

    The use of computers to represent a real-life situation, to create models.

    Models require:1. A mainframe computer to run efficiently

    2. Purpose built software (normally) as they need sophisticated software

    3. Spreadsheet software to help create the model.

    4. Inputs (where user types data) and outputs (a way of representing the system)

    There are 9 types of modelling:

    1. Economic: Used by governments to predict the future of a nations economy.

    2. Prototype: Used for testing as a physical model is built to an exact scale.

    3. Climate: A spreadsheet software is used to represent the data collected by thesensors.

    4. Weather forecasting: Used to calculate the weather predictions thanks to dataachieved by sensors.

    5. Simulations: Used to replicate a situation where the user is in control, for example

    an aeroplane.6. Profit forecasts: Used to predict future situations in a business economy in order to

    achieve more profit

    7. Architecture: Used to design structures thanks to Computer Aided Design software.

    8. Nuclear research: Used to avoid risks when dealing with nuclear issues.

    9. Geology/predicting deposits: Used to predict the amount of raw materials in thedeposits found.

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    Market Research

    The use of ICT to collect and analyse information from the market in order todiscover the demand for a type of product or service.

    Two types:- Primary research: Customers are interviewed by the company.

    - Secondary research: Examination of data which has already been published.(cheaper)

    The use of the research on advertising media may show how effective a particularadvertisement is.

    It can also be used by governments to analyse the reaction of the people tocertain economic or legislation changes that they are planning or have planned.

    There are 3 ways of interviewing to collect the information:

    Computer-assisted personal interviewing (CAPI): When the interviewer andthe interviewee are together in the same room and they sit in front of a

    computer answering questions. Computer-assisted telephone interviewing: (CATI) Where the interviewer is

    in a call centre. The interviewee can answer by dialling a certain number.

    Computer-aided web interviewing (CAWI): Answered by logging on into acertain website which asks the questions.

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    Research applications

    When the power of a computer is used in research for science andtechnology either researching existing data or information stored in theinternet or collected data.

    3 main areas: Medicine: A lot of research is needed here in order to increase the number of cures for

    diseases. Computer models have been created to help explain what things can go wrong.

    Brain scanners have helped to understand the brain better and in order to try new drugswhich have been invented thanks to the use of a computer which helps decide what arethe most convenient ingredients. This also helps with the analysis of the genes which

    are so complex that only a computer can process them.

    Science: The research is made in things that happen around us in the world. Spaceresearch is one of the best areas. By setting a list of parameters (such that theres a

    vacuum in space) we can use the computers to help us decide what are the bestmaterials which can be used on a spaceship, what effect will certain things will have on

    the humans, etc. Universities also help in the research in areas such as psychology,biology or chemistry. Specially for achieving energy a clean way using alternative energyresources.

    Education: Research can be done to find out what education skills are effective andwhich arent and can help students become more independent and responsible for their

    own learning.

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    Online applications

    Organisations which operate online services have to have web servers(word given both to hardware and software needed to facilitate the hostingof websites) to handle transactions to customers.

    Web designers should design the websites using web- authoring softwarepackages.

    Online banking :1. The user logs on and data is transferred to the banks web server.

    2. The server looks into the server database and returns the information needed.

    3. Firewalls are all through the process, as the webpage must be secure.

    Online shopping: It should have access to a web server and a shopping cart software is used. Uses the

    same principal as online banking.

    Online booking systems: Used to book a range of items online such as holidays, plane tickets, appointments...

    Also known as computer reservation systems (CRS)

    Customers need to have access to the server, so there are security issues too, as well asinformation about each user such as requested searches or a history of the flights ortickets booked.

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    Stock control Automate systems where stock is controlled by a computer with little human input and

    manual systems where humans use the computers to help stock control. Electronic points of sale (EPOS):

    Consists of screen, barcode reader, number pad and are found on almost every supermarket.

    The EPOS system is connected to a database stored on a server which has details of the barcode number,details of the product, the number in stock, the re-order level and the re-order quantity.

    Theres a file containing details of the supplier of each product so that, when the stock number is smaller than

    the re-order level, this file is accessed and more products are asked.

    Manual systems: When stock systems take place at particular times of the year

    The system doesnt do the process for you, you still have to call to order products and compare values of stock,

    but the information is stored in a computer

    Just in time systems are when the goods are ordered so that they arrive at their

    distribution point as required, this means that less storing warehouses are needed.

    Benefits to supermarket Benefits to customer

    Goods are re-ordered automatically Less queuing

    Nobody has to be employed for thework

    Itemised bills give information to thecustomer

    The company can see a list of best-selling items

    If questions over the bill arise, theycan be resolved very quickly

    The company can identify busier

    times of the day

    Barcodes ensure greater accuracy

    of data, so less mistakes.

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    Section 6

    Digital divide Disabilities Legal & political systems

    Computer fraud Antisocial use of ict Home entertainment systems Internet auctions

    Booking systems Information services government

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    Digital Divide Gap between people able to make efficient use of ICT and those who are

    not. Introduction of technology can:

    Generate jobs

    Provide greater access to better health services.

    Health services:

    Some websites contain information about: Medicine, common ailments &how to treat them, contact details of doctors, waiting lists for hospitaltreatment. Appointments can also be booked online.

    Employment opportunities:

    ICT used in manufacturing and education, therefore skills needed to getjobs in these areas. Curriculum Vitae (CV) can be created using ICT, sent tocompanies, Broadband necessary.

    Nations: also known as global digital divide

    Large gap between third and first-world nations. Accentuates economicdivide. Poorly educated nations unable to compete efficiently.

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    Disabilities Input devices simplify computers for the disabled. Instant messaging allows

    communication. Useful for the deaf (webcams), for people with sightproblems, font can be enlarged etc.

    People who cannot move/find it difficult to leave their home: onlineshopping, banking and entertainment services available and touchscreens/voice recognition systems also make it easier for them.

    PCs have many features to help the disabled:

    Overlay or concept keyboards, purpose-built keyboards, predictive wordprocessors, speech recognition software, tracker balls, joysticks, touchscreens, head wand.

    Improvements have been made for the disabled in the

    areas of banking, booking systems, health services,

    employment and government i.e on their websites,

    their financial services, their available information andtheir special offers.

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    Legal & political systems Increased access to legal information/advice on: legal contracts, divorce, child-support

    and maintenance, power to attorney, finances etc.

    Increased involvement in focus groups. Done on message boards, using messaging ortele-conferencing.

    Advantages: broader opinions, can meet any time, no money spent on food.

    Disadvantages: Reduced interaction, moderators have no influence on discussions.

    Increased influence with political representatives:

    1. Internet forums discussion websites. Allow anonymous posting, controlled by

    administrators or moderators.

    2. Weblogs (or blogs) used to record daily lives/events considered important. Politiciansuse to get close to voters, voters can speak directly to them through blogs. Features:reverse chronological posting order, unfiltered or uncensored.

    3. Wikis software allowing anyone to make pages for own website, edited to allow othersto add information to the pages. Allow quick creation of pages and also

    links to similar politics.

    Advantage: Interactive, so people can make changes and remove errors.

    Disadvantage: gives anyone chance to give distorted opinions about anything.

    Blogs, forums & wikis have opened access to political debate to anyone who has accessto internet. Increased free speech and public participation.

    Opening the debate/broadening news base on which people base their opinion.

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    Computer Fraud Much easier to commit due to technological availability. Many different ways of committing

    fraud:1. People issuing cheques into own accounts on behalf of a company using relevant

    software.

    2. False invoices (e.g. for non-essential equipment) delivering to personal address.

    3. Identity theft (i.e. stealing a person's identity details without their consent):

    Methods - Finding personal details in bins, watching people fill in forms/listening to phone

    calls disclosing personal details, using skimming devices, intercepting post and accessingdatabases containing personal data.

    Stolen information used to:

    Apply for mortgages, credit cards and take over bank

    accounts.

    Also used for Phishing/Pharming

    To prevent this, firewalls, anti-virus and anti-spyware

    software should be installed.

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    Antisocial use of ICT Hacking

    Misuse of personal data: e.g. name, address, date of birth occupation.

    Deleting personal data: hackers send virus (logic bomb) to delete certain data, or bystealing password.

    Amending personal data: changing data to cause embarrassment throughorganisations such as hospitals, police, government security services.

    Distributing personal data

    Viruses: malicious program code made to infect computers/corrupt or delete data.

    Can be obtained through: e-mail attachments, internet `offers.Protection methods: anti-virus software, back-up systems (separate from computer)

    Spam: messages sent in bulk to use up memory capacity of server concerned. ISPsmost affected. Carried out in e-mails, instant messaging, blogs, mobiles etc.

    Cyber bullying

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    Home Entertainment Systems Home Theatre systems: Surround sound, Large/wide screen, LCD/plasma screens, blu-ray

    disks for high definition (HD)

    Satellite Television: programs transmitted via communication satellites (i.e. programsignals sent to uplink satellite dish which is pointed at specific satellite with transponder,which send signal back to receiving dish on house).

    Low Noise Blockdown (LNB) converter strengthens weakened signal. Receiver boxdecrypts signals, enabling viewer to see programs.

    Terrestrial Television: also known as broadcast television. Programme providers transmitprogram signal using large aerial/antenna from broadcast centre, using transmitter to

    gather and combine signals to travel long distances. Cooling systems needed.

    Music Centres: equipped with: frequency modulation, CD player, amplifier, speakers,universal serial bus (USB) port, memory stick, secure digital (SD) memory card etc.FMfrequency modulated transmission, AM amplitude modulated transmission.

    Portable or personal stereo systems: not all able to receive FM broadcasts, as some canonly receive transmissions served by a digital audio broadcasting (DAB) tuner. Some come

    with electronic programming guide (EPG) allowing them to store stations. Interactive Games Consoles: sophisticated graphics requiring powerful processors and

    graphics engines. Can play people around the world with correct hardware links to internet.

    Video-on-demand systems: allows viewing of videos over network. Either constanttransmission or downloaded to set-top box. Can also be received through internet, mobilephones, and portable media players. Video server can be LAN or WAN.

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    Internet AuctionsSites that allow people to buy and sell their own things over the internet in an auction.

    Necessary equipment: PC, modem or broadband connection, internet browser. Features of sites: Account registry facilities, item browsing, search facility, help menu,

    option to `watch progress of desired items etc.

    Advantages: Sellers can sell unwanted clutter without hassle. Purchaser can possible buyitems for lower price than shops. Worldwide market. More available goods.

    Problems: Site cannot be held responsible for quality of goods. Returning is difficult. A lot

    of scammers on sites. Buyers can get carried away, spending much more than intended. Online transaction services: Many e-commerce businesses that allow payments to be

    made through auction sites as intermediaries between buyer and seller, such as Paypal.Security of sites assured by yellow padlock on internet window. Site enforced byencryption, thus safer for money transfer.

    Goods may be intercepted by hackers who

    have accessed address details, but unlikelydue to security of most sites.

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    Booking systems Online booking systems offer: immediate confirmation, no double bookings, printing of e-

    tickets, virtual tours.

    Airlines: online bookings/check-in, e-tickets, hotel/rental car reservations.Site features: home page, booking details, available flights, cost, customer details andpayment options, checking in facilities.

    Travel agents: can use off the-shelf or purpose-built software. Book tickets for individualsor businesses.

    Rail companies: customers can see/select times/routes online and book/print tickets.

    Cinema computer-based booking systems: allow cinema owners/managers to cut costsand increase profits. Can buy tickets online, over the phone or at kiosks in the cinemas.

    Theatres: safe bookings with e-mail address/unique code linked with tickets.

    Appointment booking systems: for booking appointment with doctors, hairdressers,dentists etc. either online, over phone or through e-mail.

    Advantages to companies: less rent for premises, fewer staff needed, larger market.

    Advantages to customers: no transport costs, can book any time, immediate confirmation.

    Disadvantages to companies: less personal touch, staff needs retraining, risk of fraud.

    Disadvantages to customers: must have computer and internet access, small risk ofinterception by hackers

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    Information Services Trading: less time consuming online, easier communication between countries/companies.

    Benefits: extended market, businesses can compare with wider range of suppliers. Many

    governments willing to provide information and advice on their website.

    Governments: services offered: education/learning, motoring, home and community,employment, money, tax and benefits, health/well-being, travel/transport,environment/greener living, crime, justice/the law, rights and responsibilities.

    Academic institutions: offer information on courses, extra-curricular activities,measurements of success. Requires website with well-organised e-mail facilities.

    Stocks and shares: many sites provide information on up-to-date figures of prices andstocks, allow to create a virtual portfolio/buy and sell shares without paying to see possiblelosses/gains to be made. Investors can buy stocks for a fee (varies from site to site)

    Public interest: sites which inform about a countrys rights/laws/environmental information.

    Educational research: provide teachers with information about educational research. Non-profit organisations. Provide descriptions of government policy on education, focusing on

    curriculum, assessment and initial teacher training frameworks.

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    Government Central government: inland revenue allows individuals to complete tax forms online/make

    payments.

    Information held by government sites:

    Income tax records, tax collection and payment information, budget calculations (using`what ifscenarios.

    Local government: services offered:

    Electoral register all voters details such as name, address, nationality kept.

    Local tax records record of all citizens who have paid taxes.

    Budget calculations use computer models of spending and income to calculate budgets.

    Issuing of documents: some governments offer online facilities to apply for passports,driving licences, ID cards.

    Governments and internet security: users log on to website, all sent and receivedinformation transferred through secure socket layer (SSL) which creates secure linkbetween user's browser and government server, to ensure data is not altered duringtransmission.If user forgets to log off or remains inactive for period of time, logs off automatically.Passports, ID cards computerised to such extent that can have data in form of biometricdata or held on magnetic strip. Easier to verify that they are genuine.

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    Section 7

    Internet protocols & hardware

    Network types

    Network security

    Electronic conferencing

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    Internet Protocols & Hardware

    Uses-a set of rules, and protocols whenhuman communicate with each other arebased on certain rules. The internet hardwareare those who permit the internet connection.

    Examples- TCP, the Ethernet, theHandshaking, the UDP, the FTP, the HTTP,Telnet or SSH. Network hubs, switches,routers or dedicated cabling are someexamples of network hardware.

    Applications- The internet protocols areapplied into network hardware so that theresmore security

    LANs Local Area Network and it serves a local

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    Network TypesLANs- Local Area Network, and it serves a local

    area, and it is usually housed within abuilding or a number of buildings within ageographical area. There are 4 common LANtopologies such as ring networks, bus

    networks, star networks and hybrid or treenetworks.

    Ring Networks- Each computer is connected toeach of its neighbours and data is transmittedaround the network. It has the advantage of

    performing better than a star network whentraffic is very heavy. But it has thedisadvantage that if connection between twocomputers results in the whole networkcrashing.

    Bus Networks- A bus network has each computer

    or device connected to a common spine. Itwill be good because although one of thedevices fail, the rest can continue working.difficult to identify the cause of the problem ifthe whole network breaks down.

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    Star Networks- Each computer or device connected to acentral hub or switch. advantage that if one computer ordevice fails, the rest of the network can carry on,disadvantage that if the concentrator breaks down, thewhole network will crash.

    Hybrid/Tree Networks- star networks where each hub and theserver are connected to a common bus-type backbone.This type of network topology is one where hubs at thecentre of star networks are linked to a common spine.advantage that this kind of network has is that it employsstar network advantages with those of bus networks.However, it can be difficult to wire the section together.

    An intranet is the name given to a private network thatprovides similar services to The Internet: e-mail,messaging, web pages, etc.

    However, these services are only for the users of theintranet they are private, not public (unlike Internetservices which are generally public).

    Businesses and other organisations often have intranetsfor use by their employees.

    Typical uses of an intranet would be:Viewing internal web pages (e.g. company calendars, etc.)

    Internal e-mail and instant-messaging between workers Sharing of internal documents

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    WLANs- Wireless Local Area Connection - behaves like aLAN but without wires or cables. signals are received by radiowaves or infrared signals, problem of security.

    Devices and kinds of technology that could be used with

    WLAN. For example, Wi-Fi is (wireless fidelity) the ability toconnect to a network or PC using radio waves instead ofcabling. At the same time, laptops are an optional element of aWLAN, but in order to gain the full benefit of having the mobilityafforded by such a network a laptop is desirable. Wirelessnetwork interface controller, or WNIC, performs exactly thesame functions as an ordinary NIC but communicates by

    transmitting data in the form of radio waves rather than usingcables. Wireless routers tends to look just like a normal router.The only difference would be its antenna and the lack of cablesconnecting it to the various computers on the network. Theresalso a wireless access point or WAP, and is a means ofconnecting wireless devices to a wired network. There aredifferent devices that can be used in a WLAN such as mobile

    phones, printers, PDAs or portable media players, and theresalso different methods of data transmission such as the spreadspectrum radio wave transmission or the use of infrared signals.

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    WPANs- wireless personal area network. Isone which is of very limited size and usedby one person. The preferred method of

    connection is via bluetooth. It has differentfunctions such transferring photos or, ingeneral, it does the same as the LAN cando, but only for one person.

    MANs- A Metropolitan Area Network orMAN is similar to a LAN in that it can beowned by one organisation, but it covers amuch larger area than a conventional LANand is often owned by a consortium of

    users. It can extend across a whole city butis still only accessible by the users asdefined by the organisations or consortium.

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    WANs- A wide area network or WAN is formed by connecting anumber of LANs through a router or a modem and it covers a muchlarger geographical area than a LAN or a MAN. Modems used to be the key gateway connecting LANs to a WAN. The role

    of a modem was to convert the digital data from a computer into analoguedata for transmission through telephone lines. HTTP proxy servers are special types of servers that act as a buffer

    between WAN, (usually the internet) and a LAN. The internet is a special type of WAN. It is a network of computer networks,

    it is worldwide and anyone can access to it. Extranets-An extranet is a means of extending an organisations intranet

    for use by selected people outside the organisation. The e-mail is the main means of communication over the internet. Business networks- WANs are used by businesses that need to connect

    their existing LANs together and also need access to the internet. VPN is not physically private network, as it uses the internet or another

    WAN to transmit data.

    Videoconferencing can also happen with this. A videoconference is ameans of communication between two or more different locations. In here, we can also include telephone call centres and online banking,

    booking and shopping systems.

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    Network Security

    For network security, you can have physical orsoftware security

    Physical Security-procedures are put in placeto prevent the user from gaining physical

    access to computers or the rooms where theyare kept. Securing computer rooms- If an unauthorised user

    gains access to a computer or network all the datastored there is vulnerable to being accessed andmisused.

    Security guards- normally provided by a security firmthat has been contracted to carry out the securityservices for an organisations computer facility.

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    Software security- Although physical security is important, thisdoes not tend to be the major source of intrusions intonetworked computer systems. Firewalls- These are designed purely to prevent unauthorised access.

    A firewall can be in 2 forms, hardware or software, but is often

    combined into one device. Encryption- This is the name given to the converting of data into a code

    by scrambling or encoding it. Digital certification- Digital certificates are issued by a certificate

    authority, which must be a body that both computers trust. Authentication techniques- In here, the techniques used are to have a

    user ID and a password so that a user is identified and can use hisaccount. Anti-Virus- An anti-virus software is used to find viruses and then

    remove them from the host computer. It will try to get rid of Trojanhorses and Worms.

    Chip and PIN cards- This is where people insert chip and pin cards sothat they can log on. They first have to insert the card and key in a PIN.

    Anti-spam- This kind of software security is used so that unwanted e-mails are rejected. Anti-pop-up software- This is normally used so that pop-up messages

    are blocked so that they do not appear. Blockers are written in Javacode.

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    Anti-spyware software- This is usually used toprevent anyone accessing your computer andcontrol it.

    Wired equivalent privacy of information- Its acode that anyone would have to enter whenusing a WLAN.

    Wi-Fi protected access- Its a WPA built on theWEP standard but it has a greater complexity inits encryption, with longer keys.

    H d

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    ElectronicConferencing

    Hardware-:Telephone, webcams, microphones, speakers.

    Software-3 types of software :Conference software, VOIP software, instant

    messaging. Conference software- It compresses the

    audio and video elements produced by themicrophones and webcams into packets ofdata for transmission through the computernetwork. It is carried out with a codec, andit needs a compression ratio.

    VOIP software- Its a way of having phoneconversations using internet. It has theadvantage that you can talk with anyone allover the world.

    Instant messaging- Its the exchange oftext messages across the internet in realtime between 2 or more people logged intoa particular instant messaging service.

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    Uses of electronicconferencing

    Businesses:

    Videoconferencing has been useful to those companies which have used them because itsaves a lot of money and time to people, however some employees complain that they spendtoo much time in front of a computer.

    They normally use it for certain meetings which require low assistance and little discussion ina very quick way. When a long discussion has to take place, companies still use the oldmethod of sending somebody.

    Phone conferencing and instant messaging aren't very used in this case.

    Schools: Videoconferencing here is used to bring together students from different countries and to

    understand their culture, saving money and time. Students can also, thanks to this, exchangeideas about certain topics.

    Phone conferencing helps specially disabled students which receive tuition by means of atelephone conference.

    Instant messaging between teenagers is normally used, however inside the school its not

    used as it distracts students.

    Research meetings: Videoconferencing is used specially for courses where class sizes are small and

    opportunities for discussion are limited.

    Telephone conferencing is used at some higher education institutions for researchers to stayin touch with their supervisors.

    Types of electronic conferencing

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    Types of electronic conferencing Videoconferencing:

    Advantages:

    1. No time or money spent on travelling

    2. Meetings ca be called immediately3. Its more environmentally friendly.

    Disadvantages:

    1. No direct eye contact, which is very important

    2. The quality of the video and audio can be low so there can be many interruptions

    3. Power cuts can prevent the conference from continuing

    Phone conferencing:

    Advantages:1. Less cost than videoconferencing and pretty cheap equipment used.

    2. No need to worry about how you look as people only hear your voice.

    3. Very good sound quality, unlike videoconferencing.

    Disadvantages:

    1. You cant see facial expressions so you dont really know the persons reaction to a certain piece ofinformation.

    2. Documents cant be seen3. Limited number of participants

    Instant messaging:

    Advantages:

    1. Instantaneous service

    2. Its extremely cheap so it can save both money and time for businesses

    Disadvantages:

    1 It can distract teenagers from their real lives making them stay at home rather than going outside


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