CIE IGCSE Info. Comm. Tech. Past Paper PDF - 0417

 CIE IGCSE INFO. COMM. TECH. //0417 TABLE OF CONTENTS 3 CHAPTER 1 Types and Components of Computer Systems 7 CHAPTER 2 Input & Output Devices 17 CHAPTER 3 Storage Devices & Media 19...

 CIE IGCSE INFO. COMM. TECH. //0417 TABLE OF CONTENTS 3 CHAPTER 1 Types and Components of Computer Systems 7 CHAPTER 2 Input & Output Devices 17 CHAPTER 3 Storage Devices & Media 19 CHAPTER 4 Networks & the Effects of Using them 25 CHAPTER 5 The Effects of Using ICT 26 CHAPTER 6 ICT Applications 40 CHAPTER 7 System Life Cycle 46 CHAPTER 8 Safety & Security 51 Audience CHAPTER 9 52 CHAPTER 10 Communication PAGE 1 OF 57  CIE IGCSE INFO. COMM. TECH. //0417 54 File Management CHAPTER 11 54 Images CHAPTER 12 54 Layout CHAPTER 13 54 Styles CHAPTER 14 54 Proofing CHAPTER 15 55 Document Production CHAPTER 16 55 Data Manipulation CHAPTER 17 55 Data Analysis CHAPTER 18 56 Website Authoring CHAPTER 19 PAGE 2 OF 57  CIE IGCSE INFO. COMM. TECH. //0417 1. TYPES AND COMPONENTS OF COMPUTER 1.2 The Main Components of Computer SYSTEMS Systems CPU 1.1 Hardware & Software Processing done by central processing unit Hardware Three main components: Tangible physical components of a computer system o Control unit - coordinates input and output devices You can feel it or touch it and carries out program instructions Internal Hardware Devices: o Arithmetic and Logical Unit (ALU) - performs o Processor calculations and logical comparison: A < B? o Motherboard o Immediate access store (IAS) - holds data and program o RAM & ROM instruction in current use o Video & Sound Cards Microprocessor: o Internal Hard Disk Drives o Used instead of CPU External Hardware Devices: o Single integrated circuit o Monitor Internal/Main Memory o Keyboard Stores all data: application software, operating system, o Mouse data files o Printer Consists of ROM and RAM o External Storage Devices Both RAM and ROM are integrated chips Software RAM: Programs that control computer systems o Random access memory (RAM) is an internal chip Set of instructions that make computer do something where data is stored temporarily You cannot physically touch software o Memory can be written to and read from Relates to ideas & instructions for using physical objects o RAM > ROM (usually; except washing machines) Two types of software: o Stores anything that needs to be changed Application software: o All program and data being used are on RAM o Programs that allow the user to do specific task o Contents lost when computer is turned off o Design to carry out tasks o Referred to as volatile memory o Can be general purpose software or custom-made ROM: software (specialist software) o Read only memory (ROM) is memory used to store o E.g. Spread sheets, databases, word processing permanent information System Software: o Used to contain configuration data for a computer etc. o Programs that allow the hardware to run properly o Chips cannot be altered, only read from o Control computer's hardware and application program o Data not lost when computer is turned off o Communicate with user o Referred to as non-volatile memory o E.g. Operating system, device drivers, compilers BIOS: o ROM contains boot file, referred to as BIOS (basic input/output system) o Tells computers what to do when it first starts o Does hardware check when computer is turned on o Then it loads operating system into RAM o BIOS stores date, time and system configuration PAGE 3 OF 57  CIE IGCSE INFO. COMM. TECH. //0417 Input & Output Devices Advantages Input devices: o Knowing the correct commands, this can be much o Purpose is to provide data for processing faster than any other interface type o Data is raw facts which alone have no meaning o Uses much less RAM than any other interface type o Examples: keyboard, mouse o Low resolution, cheap monitors can be used Output devices: o CLI does not require Windows to run o Displays result of processing Disadvantages o Information is processed data which has been given o Can be confusing meaning o Commands must be typed precisely, if there is a o Examples: monitor, printer spelling error the command will fail o If you mistype an instruction, it is often necessary to Secondary/Backing Storage start all over again Stores data/information & programs not being used at o Large number of commands need to be learned current time GUI - Graphical User Interface Backing store device = reader or recorder Uses graphics to stand for the complicated actions o Example: Hard disk drive Uses icons Backing store media = hardware containing data Uses a mouse to selector the icons o Example: Hard disk Screen divided into windows allows different things on Basic Computer Model each WIMP - Windows Icons Menus Pointers Advantages o Easy to use because requires little IT knowledge o Easy to explore and find your way around the system o Do not have to learn complicated commands o Exchange data between different software o Good help facilities provided with GUIs Disadvantages 1.3 Operating Systems o Larger amount of hard disk space than other interfaces Enables users to communicate with computer systems o Significantly more memory (RAM) to run than other Controls operation of input, output & backing storage interface type Supervises loading, running & storage of application o GUI use more processing power than other types of program interfaces Deals with error in application programs o GUI can be slow for experienced programmers to use, Maintains security of whole computer system they find CLI much faster Maintains a computer log Two main types of interfaces: CLI & GUI 1.4 Types of Computers CLI - Command Line Interface Desktop/Personal Computers Types commands to tell the computer what to do Refers to general purpose computers o The user must know all the commands PC refers to IBM compatible computers, distinguishing o Must not make typing errors them from the Macs Used by technicians Made up of separate monitor, keyboard, mouse and Can access everything on the computer system processing unit GUI users can only access places they have icons for Advantages o Spare parts standardized results in low costs o Tend to have better specifications o Large casing allows good dissipation of heat build up PAGE 4 OF 57  CIE IGCSE INFO. 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TECH. //0417 Disadvantages Smartphone o Not portable since they are made up of separate Modern phones that can perform similar tasks to all the components above o Wiring clutters up desk space Main use of smartphones is social media & day-to-day o Necessary to copy files as they aren't portable planning Laptop/Notebook Computers Use varies from person to person Refers to computers where monitor, keyboard, pointing Advantages: device and processor together in a single unit o Smallest lightest most portable Extremely portable systems o Integrated/virtual keyboard o Low weight o Often the least expensive device o Low power consumption o More practical for day-to-day use o Processor doesn't generate too much heat Disadvantages: Advantages o Small screen may be difficult to use o Portable because monitor, pointing device, keyboard, o Not as powerful as other devices processor & backing store units are together in one box o Often has the lowest battery life o No trailing wires o Small size makes it easy to steal/lose o Full advantage of Wi-Fi o Can link into any multimedia system 1.5 Impact of Emerging Technologies Disadvantages This is technology that is being newly developed o Easy to steal These can have several impacts on our society o Limited battery; need to carry charger Artificial Intelligence (AI) o Keyboard and pointing device awkward to use Technology that focuses on creating a computer system o Heat dissipation is difficult due to laptop structure that can closely mimic or simulate human intelligence Tablet Computer AI can be used to: These are small hand-held devices that can perform o Enhance video games and computer tactics many functions that PCs & laptops do o Help decision making steps in expert systems Often use touch screens to operate o Make robots to imitate human behaviour On-screen virtual keyboard replaces physical keyboard o Understand different human languages Often used by graphic designers to digitalize their Impact on everyday life: content with a stylus pen o Can be used to accurately predict hazardous weather Can be used like a PC and/or a Smartphone conditions and signal warnings automatically Advantages: o Take over menial tasks for humans; increasing our o Small light & portable leisure time o Built in cameras for photos & videos o Can be used for safer automated travel; cars that can o Touchscreen can be used with a stylus pen drive and park by themselves o Long battery life o Increases home safety by being able to tell the Disadvantages: difference between owner & intruder; call authorities o Less storage spaces automatically o Lacks power of laptop/PC o Improved medical care as decision making skills and o Digital keyboard can be difficult to use precision can be enhanced o Touchscreen may be difficult to use for detailed work PAGE 5 OF 57  CIE IGCSE INFO. 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TECH. //0417 Biometrics Impacts on everyday life: A part of a person’s body is used to identify that o Increased personal time since robots can take over individual domestic chores Can be: o Increased manufacturing efficiency since robots are o Fingerprints much faster and less expensive than human labour o Retina o Unemployment as robots replace humans in o Iris autonomous jobs o Face o Safer working environments since robots can perform o Voice tasks that are too dangerous for humans These are all unique to everyone thus can be used as an Quantum Cryptography authentication technique Technology that allows messages and data to be sent Must be added initially to a system to use as with complete privacy; basically, advanced encryption identification Older encryption is based on mathematics, but this new Impacts on everyday life: tech uses physics o Better security at the airport since most use at least Makes it much more complex to decrypt one form of biometric check if not more Impacts on everyday life: o Increased security in certain places as only authorized o Completely secure voting ensuring that votes cannot personnel can gain entry be tampered with or changed o Reduced vehicle theft since newer car doors come o Completely secure communication eliminating the risk with a fingerprint lock on the door handle of being read/heard by the wrong eyes/ears o More secure mobile devices as most now have some o Completely secure bank transactions so money goes sort of biometrics integrated into them exactly where it is intended Vision Enhancement o Completely secure personal information preventing LVES: low vision enhancement systems: video projected hackers access to intrusive details about a person inside a headset in front of the user’s eyes. Brings the Computer Assisted Translation (CAT) objects closer for the viewer. When human translators use computer software to help NVE: Night vision enhancement: amplifies visible and in the translation process infrared light. Light passed through image intensifier Can reduce translation time tube where light is converted to electrons, then May not be 100% accurate amplified (increase in no.) and then light up screen with Common CAT tools: phosphor dust. o Spell checkers Robotics o Translation memory software Programmed machinery widely used to do physically o Language search-engine software demanding tasks Impacts on everyday life: Can be automated or manually operated o More accurate documents since most software can Used to perform several tasks: automatically detect errors o Dangerous jobs such as bomb disposal o More multilingual society since anyone with an o Exploring extreme environments such as volcanoes internet connection can now essentially learn multiple o Repetitive manufacturing jobs such as welding languages using translators o Moving heavy objects such as large engines o Quicker translations 3D & Holographic Imaging Technology that makes images appear to be 3- dimensional by adding a layer of depth Holograms use 2 regular 2D images and manipulate them to produce a 3-dimensional image PAGE 6 OF 57  CIE IGCSE INFO. COMM. TECH. //0417 Different laser beams are used to record the 2D images onto a single photographic plate 2. INPUT & OUTPUT DEVICES This creates an illusion of one 3D images Impact on everyday life: 2.1 Input Devices & their Uses o Improved security since majority of credit/ID cards & Keyboards bank notes use holograms to prevent forgery QWERTY- layout o Better movie experiences since 3D viewing can provide Ergonomic- reduces a more immersive experience for the audience health related problems o Greater data storage since holographic layers can Uses potentially decrease the thickness of disc storage o Keyboards are used Virtual Reality (VR) to input data into application software When computers create an artificial environment that o Also used to for typing commands to the computer users can virtually interact with (CTRL + P) Uses: Advantages o Allow architects to walk around a virtual version of o Enables fast entry of new text into a document their design o Well-tried technology & well-known method of entry o Training soldiers for combat by allowing them to fight o Most people find them easy to use against virtual enemies o Easy to do verification check as data is entered, as it o Training surgeons by allowing them to operate on appears on the screen simultaneously virtual patients Disadvantages o Playing games and enhance the level of immersion o Users with limited arm/wrist use can find keyboards General VR equipment: hard to use o Eye goggles that produce 3D images to develop the o Entering data is slow when compared to direct data artificial environment entry (e.g. Optical mark recognition) o Special gloves or controllers to perform precise actions o They use up desk space as they are quite large inside the simulation Numeric Keypads o Headphones to control what is heard in the virtual A numeric keypad is used to world enter numbers only o Powerful computer to run the entire VR system in real Although some have function time key to allow input of alphabetical Impacts on everyday life: characters o Improved medical surgeons/soldiers Uses o Stronger buildings o Used in Automatic teller machines (ATMs), where o Treatment of phobias as certain situations can be customers can key in their personal identification treated using simulations number (PIN), or an amount of money o More realistic education as students can learn in a o Used to key in phone numbers into telephones more interactive environment o Electronic point of sale (EPOS) terminals have numeric keypads in case the barcode reader fails o Used in Chip and PIN devices to key in PIN, or amount of money o Used to enable fast entry of numeric data into a spread sheet Advantages o Numeric keypads are faster than standard keyboards for entry of numeric data o Since many are small devices (e.g. mobile phones), they are easy to carry around PAGE 7 OF 57  CIE IGCSE INFO. 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TECH. //0417 Disadvantages Advantages o Can be difficult to use due to the very small keys o Faster to select an option by a touchpad than a o Difficult to use for entering text keyboard o Sometimes the order of numbers isn’t very intuitive o Enables rapid navigation through applications and the Mouse internet An example of a pointing device o Since the touchpad is integrated into laptop computer, The ball underneath the mouse is used to detect there is no separate mouse, aiding portability movement o They can be used when no flat surfaces are available The left button is for selecting by double on it and the Disadvantage right is to bring drop-down menus o People with limited hand/wrist movement can find There is usually a scroll button which speeds up the touchpads hard to use process of moving through a document o It can be more difficult to control the pointer when Uses compared to a mouse o Used for opening, closing and minimising software o They are more difficult when doing operations such as o Used for grouping, moving and deleting files ‘drag and drop’ o Useful when editing images (e.g. controlling the size Tracker Ball and position of the image) Tracker ball is like a mouse o Used for controlling the position of a pointer on the except that it has a ball on the screen to allow: top of the device ▪ Selection from a menu Users control the pointer on the ▪ Selecting an icon screen by rotating the ball ▪ Scrolling up/down and right/left Uses Advantages o Have the same pointing/cursor control capability as a o Faster to select an option by a mouse than a keyboard mouse o Enables rapid navigation through applications and the o Used in applications where the user has a disability internet (RSI) o Mice are small and don’t take much area o Used in a control room environment, where it is faster Disadvantages than a mouse to navigate through process screens and o People with restricted hand/wrist movement can find more robust than a mouse it hard to operate a mouse Advantages o Easily damaged and can easily be clogged up with dirt o Tracker balls don’t need the same fine control as a o They are hard to use if there is no flat surface available mouse Touchpad o People with limited hand/wrist movement find easier Touchpads are used in many laptop computers as a to use than a mouse pointing device o The pointer can be positioned more accurately on the The pointer is controlled by the user moving their finger screen than with a mouse on the touchpad o They take less desk space than mice since they are Uses stationary o Used for opening, closing and minimising software Disadvantages o Used for grouping, moving and deleting files o Tracker balls are not supplied with the computer as o Useful when editing images (e.g. controlling the size standard, so they are more expensive and position of the image) o User may need training since they are not standard o Used for controlling the position of a pointer on the equipment screen to allow: ▪ Selection from a menu ▪ Selecting an icon PAGE 8 OF 57  CIE IGCSE INFO. 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TECH. //0417 Remote Control Use A remote control is used to control the operation of o Used for service tills e.g. petrol stations other devices remotely by using infra-red signals o Used where selections are made on a screen e.g. Uses ATMs, public information systems, airports and railway o In home entertainment devices such as Televisions, stations DVD player/recorder and satellite system o Used in PDA’s o Used to control multimedia systems o Used in Interactive white boards o Used in industrial applications to remotely control o Used in computer based training (CBT) processes, stop and start machinery Advantages Advantages o Enable faster entry of options than a keyboard/mouse o Enable devices to be operated from any distance, ▪ Very easy to choose options which is useful for people with disabilities ▪ User friendly method for inputting data o Some chemical processes are hazardous, so it is safer ▪ They are tamperproof, preventing people from to operate equipment from a distance keying in information (which could corrupt the Disadvantages system) o People with limited hand/wrist movement can find Disadvantages them hard to use o There is a limited number of options available o The signal between the control and the device can be o Using touchscreens often can lead to health problems easily blocked e.g. (straining of arm muscles and RSI) Joystick o The screen can get very dirty with constant touching By gripping the stick, a pointer Scanners on the screen can be controlled Used to input information on hardcopy e.g. text Buttons are used to make document selections Uses Uses o Used to scan in documents and convert them into a o Video/computer games are format for use in various software packages often controlled by joysticks o Old and valuable documents and books can be o They are used in simulators to mimic actual controls scanned, protecting the original copies from damage Advantages o Non-digital photographs can be scanned for storing on o Easier to navigate round a screen compared to a a computer keyboard Advantages o Control is in three dimensions o Images can be stored for editing later Disadvantages o Scanners are much faster and more accurate than o More difficult to control the on-screen pointer with a typing in documents again joystick than with other devices such as mice o It is possible to recover damaged documents and Touch Screen photographs by scanning them and then using User can choose an option by simply touching a appropriate software to produce an acceptable copy button/icon on the screen Disadvantages The selection is automatically made without the need for o The quality can be limited depending on how good the any pointing device scanner resolution is PAGE 9 OF 57  CIE IGCSE INFO. 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TECH. //0417 Digital Cameras Advantages Photographs are stored in memory Faster to read in text than to type it using a keyboard They can be easily transferred to a computer using a USB o Possible to manipulate sound in real time using special Uses software o Digital cameras can produce o If used in a voice activation system, this has the photographs for direct transfer advantage of improving safety to a computer or to print out Disadvantages o Digital cameras allow short o Sound files can use up a lot of computer memory video clips to be produced o Voice recognition software isn’t as accurate as typing o Photographs can be uploaded directly into application in manually software such as word processor Sensors Advantages TYPE OF SENSOR APPLICATIONS o Easier to produce better quality photographs than TEMPERATURE Automatic washing machines, with a tradition camera central heating systems, o Easier and faster to upload photographs to a computer automatic green houses, ovens o There is no need to develop film and print out PRESSURE Burglar alarm systems, robotics, photographs (saves paper and no longer needs the environmental monitoring, chemicals to produce photographs from films) Automatic washing machines o Easy to delete an image from the memory if it’s not LIGHT Automatic doors, street lighting satisfactory control, Burglar alarm systems, o The memory card can store several hundred automatic greenhouses photographs SOUND Burglar alarm systems, Disadvantages monitoring liquid and powder o The camera user needs to be computer literate to use flow in pipes the camera properly HUMIDITY/MOISTURE Automatic greenhouses, o There is some artistry lost since clever software environmental monitoring, corrects errors in the photographs factories where moisture levels o The resolution is not yet as good as traditional are crucial cameras PH Automatic greenhouse, chemical o Images often need to be compressed to reduce the processes, environmental amount of memory used monitoring o It is possible to fill up computer memory very quickly Advantages with several photos of the same subject (to find the o Readings by sensors are more accurate than taken by perfect snap shot) humans Microphone o Readings are continuous, there is no break in Can be connected directly to a monitoring computer o Because it is a continuous process any necessary Sounds can be inputted and action or warning will be initiated immediately manipulated o The system can be automatic, removing the need for Uses human intervention, this is particularly important if the o Microphones are used to input speech/sounds to be process is hazardous used in various applications Disadvantages o They are used in voice recognition software- for o Faulty sensors can give spurious results conversion of speech into text, and recognition of commands PAGE 10 OF 57  CIE IGCSE INFO. 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TECH. //0417 Graphic Tablet 2.2 Direct Data Entry & Associated Devices A graphic tablet is used with a stylus to produce Magnetic Stripe readers freehand drawings Used to read information on the Uses magnetic stripe o Graphics tablets are used to The stripe contains useful produce drawings, computer information such as start and graphics expiry date o In countries where characters are complex e.g. japan Uses they are used as a form of input o Credit and debit cards have magnetic stripes that are o They are used in computer aided design (CAD) work used by ATMS or EFTPOS (electronic funds transfer point of sale) terminal Advantages o Security cards for entering building e.g. hotel rooms o It is possible to modify drawings before they are input o Travel systems e.g. train and underground tickets o They offer an accurate method of drawing Advantages Disadvantages o Data entry is fast compared with keying in using a o They are more expensive than other pointing devices keyboard or keypad Video Camera o System is error free, no typing involved DV (digital video) camera store compressed photo o Information is secure since there is no typing and the frames at 25 MB/s – motion jpeg. information can’t be read directly by a person Light turned into electronic signal through light sensitive o Can prevent access to restricted/secure areas sensors and automatically converted to a digital file o Magnetic stripes are unaffected by oil water and format. moisture Advantages: o No moving parts therefore physically robust o Easy to edit footage in a video editing. Disadvantages o High quality video captured, therefore o If the magnetic stripe is damaged the data is lost Disadvantages: o Card needs to be in close contact with the reader o Storage medium (Memory cards) more expensive to o Since the information is not human readable, they buy than films. need to find a way to show the information to the Web Cam customer (e.g. hotel room number not printed on Connected directly to a computer cards) via a USB port Chip & PIN readers Uses The device has a slot where o While chatting online webcams the card is placed, and the can be used to have chip is read conversations A small screen is part of the o Used to enable video reader which gives conferencing to take place instructions to the operator Advantages Uses o Can be left on constantly and activated when required o Chip and PIN readers are o Allow people to keep in contact with each other used where payments are made using cards e.g. travel without the need to travel, particularly useful for agents disabled or elderly people Disadvantages o Webcams have limited features and the picture is often of poor quality o They need to be connected to a computer PAGE 11 OF 57  CIE IGCSE INFO. 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TECH. //0417 Advantages Disadvantages o Provide a more secure payment system than requiring o Only certain characters can be read, and the number a signature or using magnetic stripe, since the PIN of different characters is very limited typed in must match up with the PIN stored on the chip o It is a more expensive method than other methods o Provide a more robust system than magnetic stripe used for direct data entry since the chip does not need to be in contact with the Optical Mark Reader reader Optical mark recognition is a Disadvantages system which can read marks o Customer needs to be careful when typing in the PIN, written in pen or pencil so nobody reads it giving an opportunity for Fraud Uses Radio Frequency Identification (RFID) Readers o OMR devices are used to RFID readers work in similar ways to a bar code reader read questionnaires, multiple choice examinations An RFID tag is attached to/inside a surface papers and other types of forms in the form of lines or The reader reads the data held on the tag which is then shaded areas input into the computer system for processing Advantages Radio waves are used to transmit data thus can be used o A very fast way of inputting results of a survey through most materials o Since there is no typing, it is more accurate than Uses keying in data o Used in retail or supermarkets as barcode alternatives o OMR is more accurate than OCR o Used to identify pets Disadvantages o Used in passports o Forms need to be carefully designed to make sure that Advantages the marks/shadings are correctly positioned to gather o Can hold a lot of data accurate information o Can be read from long distances o There can be problems if forms aren’t filled correctly, o Does not require direct line of sight sometimes they must be checked manually before o Information can be read faster than barcodes being read by an OMR, this is both time consuming and o Can alter information expensive Disadvantages Optical Character Reader o Thieves can steal information easily Optical Character recognition is o RFID tags are expensive a software that takes scanned o Radio waves can experience interference text and converts it into a Magnetic Ink Character Reader computer readable form (MICR) Uses Magnetic ink character recognition o Processing of passports and Identity cards is a system which can read o OCR is used when scanning documents to modify them characters printed in a special ink using a suitable software Uses Advantages o Used to process cheques in banking operations – o Much faster data entry system than manually keying in cheque is read using a batch processing method data Advantages o Since there is no manual data entry, the number of o MICR offers great security than OCR since the oriented errors is reduced characters cannot be altered Disadvantages o There is no manual input, thus errors are reduced o The system has difficulty reading handwriting o If somebody writes over the magnetic ink characters, it o It is still not a very accurate technique can still be read PAGE 12 OF 57  CIE IGCSE INFO. 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TECH. //0417 Barcode readers Advantages Used to read information in the o Produce higher quality images than TFT monitors form of a barcode o Angle of viewing is better than a TFT monitor Handheld scanners or wands are o They work with light pens in CAD and CAM very common for reading applications (Computer Aided Design/Manufacturing) barcodes Disadvantages Uses o Tend to be heavy, weight hazard if not supported o Used in supermarkets and other shops where the properly goods are marked with a barcode o Run very hot, can cause fires if left unattended – o Used in libraries to scan user’s library card and especially if they are old barcodes on books (to keep track of books on loan) o Consume more power than TFT monitors o Used as a safety function in many companies to ensure o They can flicker, this leads to headaches and eyesight that electrical equipment is checked on a regular basis problems with prolonged use Advantages TFT Monitor o Faster than keying in information, and fewer mistakes Thin Film Transistor monitors are made Taking over from CRT monitors as the o Used as a way of recording data, can improve safety main output device o Barcodes enable automatic stock control The progress in TFT technology is one o Barcode scanning is a tried and trusted technology of the reasons for the rapid development of laptop o When an item price is changed, only the central computers database needs to be updated, there is no need to The screen is made up of thousands of tiny pixels which change the prices individually on each item are made up of transistors controlled by a Disadvantages microprocessor o Barcode scanning is an expensive system to administer Each pixel has three transistors-red, green or blue; the since every item in the shops needs a barcode and intensity of each determines the colour of the pixel seen. every barcode needs to be entered on the system Uses o Also, there is a need to invest in the computer o Primary output device for computers, user can technology together with staff training, which can all immediately see what they are typing in be expensive o Integral part of laptop computers o The system is not fool proof- barcode can be swapped Advantages around on items o Lightweight, so no weight hazards like CRT monitors o Less glare produced than in CRT monitors; also emit 2.3 Output Devices & their Uses less radiation CRT Monitor o Consume much less power and generate less heat Cathode Ray Tube monitors than CRT monitors Least expensive type of monitor, becoming rarer as TFT Disadvantages monitors take over o Angle of viewing is critical, image appears unclear if Come in various sizes viewed slightly from the side Picture created is made up of tiny dots (red green or o This is an issue if several people are looking at the blue), the intensity of the colour of the dot determines screen at the same time the colour perceived by the eye o They cannot yet be used with light pens, Uses o Primary output device for computers, user can immediately see what they are typing in o Used with light pens to allow designs to be created on screen PAGE 13 OF 57  CIE IGCSE INFO. 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TECH. //0417 IPS/LCD Monitor Multimedia Projector Front layer made from liquid crystal diodes; grouped Receive analogue and digital together to form pixels (RGB or RGBY-more vivid colours) signals, although most modern Receive analogue and digital signals, although most projectors only work with digital modern projectors only work with digital inputs inputs IPS (In-plane switching) is the technology used in LCD The signal source is usually from a computer, television, monitors. or DVD player Advantages: The image from the source is magnified and projected o Colour can be seen accurately from different viewing onto a large screen angles The devices usually work with a remote control, but can o No lightening on touching also use virtual mouse technology – cordless PC mouse Disadvantages: (has a laser pointer) o Expensive o It is then possible to direct the presentation without o High power consumption being tied to the computer o Slow response time o Most multimedia projectors take input from various Note: Old LCD monitors used CCFL (cold cathode types of video format e.g. PAL, NTSC or SECAM fluorescent lamp) technology to light up the screen. Uses LED Monitor: o Used for training presentations (allows the whole Front layer made from liquid crystal diodes; grouped audience to see the images from a computer) together to form pixels (RGB or RGBY-more vivid colours) o Also used for advertising presentations (shown at For the image to show up on-screen a light source of LED exhibitions, shopping malls etc.) backlight is used. o Home cinema systems (projecting the images from a Advantages (over LCD monitors): DVD or television) use multimedia projectors o Lighter and thinner Advantages o Longer life o Enables many people to see a presentation rather than o Lower power consumption all of them crowded around a small computer screen o Greater contrast and more vivid colour o Avoids the need for several networked computers o Relatively more robust o e.g. when looking at a video clip on the internet, Disadvantages: everybody can see the video on the large screen rather o Glare gives viewers headaches than logging on to several computers o Images too sharp, so can cause eye strain Disadvantages Touch Screen o Images can sometimes be fuzzy Automatic selection without a pointing device o Expensive to buy Uses: o Setting up projectors can be a little difficult o Automatic teller machines o EFTPOS (electronic fund transfer point of sales) Laser Printer o PDA Produce very high-quality hard copy o Smartphones output o Public information points Print rate per page is fast if many ADVANTAGES DISADVANTAGES pages are being printed Faster data entry Limited options Rely on large buffer memories – the Easy to choose Frequent usage can lead to RSI, data for the whole document is stored options etc. before pages can be printed out User-friendly and Constant usage results in the intuitive screen getting dirty; visibility and sensitivity decreases PAGE 14 OF 57  CIE IGCSE INFO. 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TECH. //0417 Uses Disadvantages o Used where noise levels need to be kept low e.g. in an o Output is slow if several copies needed – there is little office buffer capacity to store the pages o The best option for fast, high quality, high volume o The ink cartridges run out too quickly to be used for printing large print jobs Advantages o Printing can smudge if the user is not careful o Printing is fast for high volumes, slightly faster than o Can be expensive to run if they are used a lot – original inkjet if only a few pages are to be printed ink cartridges are expensive o Can handle very large print jobs Dot Matrix Printer o Quality is consistently high A type of impact printer o Toner cartridges last for a long time; laser printers can A print head made up of a matrix be a cost-effective option if colour outputs are not of pins presses against an inked required ribbon Disadvantages Uses o Expensive to buy o Can be used in noisy environments e.g. garage o Only fast if several copies are being made workshops o Colour laser printers tend to be expensive to run since o Can be used in applications were the print quality is four cartridges are needed as well as diffuser kits, etc. not very important o Produce ozone and volatile organic compounds Advantages because of their printing method and type of toner/ink o Can be used in environments which would be a used problem for laser and inkjet printers – dusty, dirty or o These have been linked to health hazards in the office moist atmospheres Inkjet Printer o Carbon copies or multi-part outputs can be produced Used to produce good quality hard o Very cheap to run and maintain copies – the quality is not as good as in o Easy to use if continuous stationary is required e.g. laser printers but much better than long print jobs such as wage slips that of dot matrix printers Disadvantages Do not have large buffers like laser o Very noisy – not good in an office environment printers, so printing is done a bit at a time o Cost more than an inkjet printer to buy Therefore, printing is sometimes paused – the whole o Very slow page can’t be stored in the buffer, it must wait for the o Printing is of poor quality computer to send more data Wide Format Printer Uses Devices that produce hard o Used where low volume outputs are needed copies but operate in a o Ideal for high quality printing for small print jobs or different way to printers single pages e.g. for photo quality printouts Not limited to normal printer Advantages paper size and can produce o High quality output highly accurate, very large o Cheaper to buy than laser printers drawings and posters o Very lightweight and take up little space (small The most common types are footprint) pen plotters, electrostatic o Do not produce ozone and volatile organic (similar method to laser printers) and inkjet plotters compounds, unlike laser printers o With pen plotters, coloured pens are controlled by a computer and the paper can move backwards and forwards to allow accurate shapes to be drawn PAGE 15 OF 57  CIE IGCSE INFO. 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TECH. //0417 Uses Speakers o Used to produce large drawings e.g. blueprints of Can be connected directly to a computer or are built into buildings; are often used with CAD applications the monitor or casing (as in o Used to produce large pictures for use on billboards or laptop computers) giant posters Uses a digital to analogue ▪ They can also print on plastic coated paper converter (DAC) to convert digital If the pens are replaced by cutting tools, it is possible to data from the computer to analogue from so the make large signs speakers can process it; the signal is then amplified Advantages through the speakers. o Can produce huge printouts Uses o Print quality is extremely high o Used to output sound from multimedia presentations Disadvantages o Used in home entertainment centres o Slow in operation o They can help blind people through audio output of o Expensive to buy and maintain text on the screen (together with speech generation 3D Printer software) A new type of printer that o Used to play downloaded sound files produces solid 3D models using Advantages modified inkjet technology called o Usually long lasting and durable (if operated within tomography their intended power levels) Very thin layers of fine powder o Often provided with the computer/laptop although (plaster, resin, starch) are bonded together as a 3D these may not be the best quality model is slowly built up Disadvantages Items produced are known as prototypes o Can take up a lot of desk space, compared to Uses headphones o Used to produce prototypes which work from CAD o Can distract people around you, everyone can hear packages, photograph images, stored drawings etc. what you are playing o Scale models are produced in colour before the real o May not be able to hear the full sound spectrum, this thing is manufactured requires multiple speakers o The ultimate objective is to produce organic objects Actuators using this layering technology (such as replacement A type of controlling device human organs) Transducers that are used to take signals from a computer and convert them into some form of motion Advantages e.g. operating motors, pumps, switches and valves o Save a lot of money, other methods of making Digital signals are sent from the computer to an actuator prototypes are very time consuming and expensive to operate a device o The powders used can often be ground up and reused Conversion of the digital signal to analogue is required o Physical scale models are produced with working first (using a DAC) parts, which gives a better idea of how the product will look Disadvantages o Expensive to buy o Slow at producing their output o Product is sometimes a little rough, often further work needs to be done PAGE 16 OF 57  CIE IGCSE INFO. COMM. TECH. //0417 Motors Turned on or off by the actuator 3. STORAGE DEVICES & MEDIA Uses o Used in many domestic appliances 3.1 Magnetic Backing Storage Media o Automatic washing machines (to Fixed Hard Disks/Drives make the drum rotate) Available on all computers and is the main method used o Cookers (to switch on fans) for data storage o Water pumps in central heating systems Uses a read/write head to write and read data from it o Automatic greenhouses to open windows and switch Disk surface coated in magnetic film, storage is done by on fans altering binary codes to 1s or 0s o Used to control robot arms in the industry Uses o Operate fans, disk drives and DVD drives in computers o Used to store operating systems and working data Buzzers o Used for storing application software Switched on or off by the actuator o Real time systems and online systems used fixed hard Uses drives o Used in cookers and microwave ovens to tell the o Used in file servers for computer networks operator when the cooking process is complete Advantages o Used in burglar alarm systems to warn if intruders are o Very fast data transfer rate and fast access times to present data Heaters o Have very large memory capacities Actuators are connected to switches which turn the Disadvantages heater on or off o Can be easily damaged Uses o They lack portability o Used in automatic washing machines, cookers and Portable & Removable Hard Disks/Drives central heating systems Like fixed hard disks but are usually connected via o Used in automatic greenhouses to control the universal serial bus temperature Uses Lights o Can be used as backup systems to prevent loss of data The actuator is connected to the switch that turns the o Can be used to transfer data, files and software lights on or off between computers Uses Advantages o Security lights o Data access time and transfer rate is very fast o Used in greenhouses to control the lighting conditions o Large memory capacities o Can be used to transfer information between computers Disadvantages o Can be easily damaged Magnetic Tapes & Drives Thin strip of plastic which is coated in a magnetic layer Read and written by read/write head Uses o Application where batch processing is used o Used as a backup media Advantages o Generally, less expensive and very robust technology o Data transfer rate is fast PAGE 17 OF 57  CIE IGCSE INFO. 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TECH. //0417 Disadvantages Advantages o Access time is very slow o Cheaper than RW disks o When updating another tape is needed o Once burned (and finalized) they are like ROM Memory Cards Disadvantages A form of electrically erasable programmable read only o Can only be reordered once memory (EEPROM) o Not all CD/DVD players and can read CD-R Uses CD-RW/DVD-RW o Used to store photos on digital cameras ‘RW’ means that these disks are re-writable media can o Mobile phones use them as memory cards be written over several times o Used in MP3 players to store music Unlike CD-R/DVD-R they don’t become ROMs o Used as a backup in hand held devices The recording layer uses a special phase-changing metal Advantages alloy o Very compact The alloy can switch between crystalline and amorphous o Very robust (non-crystalline) phases, thus changing its reflectivity to Disadvantages light, depending on the laser beam power o Very expensive per Gb of memory when compared to Spots are produced which can be read by a laser hard drive disks System allows data to be written, erased and re-written o Has a finite life in terms of the number of times they many times can be read from/written to. Uses o CD-RWs and DVD-RWs are used to record radio and 3.2 Optical Backing Storage Media television programs CD-ROM/DVD-ROM o They are used in closed circuit television (CCTV) Read only memory – cannot be overwritten systems Data is stored as a series of pits and lands formed by a Advantages laser beam etching the surface at manufacturing stage o Can be re used many times Uses o Different file formats can be used each time o Store music files and software. o Less wasteful than R format since files or data can be o Very large storage capacity and are used to store films. added at a later stage Advantages Disadvantages o Holds more data than floppy disks o Relatively expensive media o Less expensive than hard disk drives o Possible to accidentally overwrite Disadvantages DVD-RAM o Data transfer rate and data access time are slower Recent addition to optical media group CD-R/DVD-R Unlike other CD and DVD formats, DVD-RAMs have The letter ‘R’ means the disc is recordable only once and several discrete concentric tracks rather than a single then it becomes ROM spiral track Use a thin layer of an organic dye as the recording media Gives them advantage that writing, and reading can DVDs also use an additional silver alloy or gold reflector occur at the same time Laser beam produces heated spots and unheated spots Makes it possible to watch an already recorded Uses television program at the same time as a different o They are used for home recording of music (CD-Rs) program is being recorded and films (DVD-Rs) Recording layer is made from similar phase-changing o They are used to store data for later use material to that used in RW technology o Used in applications where it is necessary to prevent Shiny and dull marks represent data to a computer the deletion or over-writing of important data where they are interpreted PAGE 18 OF 57  CIE IGCSE INFO. 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TECH. //0417 Uses Built with an array of semiconductors that form its o DVD-RAMs are used in recording devices such as memory and operated using an integrated circuit satellite receivers to allow simultaneous recording and Uses playback o Used to store operating systems and working data o They are used in camcorders to store films o Used for storing application software Advantages o Used in file servers for computer networks o Have a long life (30 years) Advantages o Can be re written on more than the DVD-RWs o Faster than hard disks because they do not need to (100,000 times) ‘spin up’ the disk o Very reliable as they have built in verification software o Robust because no mechanical parts to ensure accuracy of data o Read performance is fast even when data fragmented o Access is very fast o Less susceptible to data loss o No need to finalize the disk o Lighter, quieter and require less power than hard disks o Very large capacities Disadvantages o Ability to read and write data at the same time o More expensive than hard disks Disadvantage o Have a smaller capacity than modern hard disks o DVD-RAMS are not as compatible as R or RW, many o Lower number of write cycles causing performance to systems will not recognize this format diminish over time o More expensive than DVD-RW Flash Drives Blu-Ray Discs Otherwise called pen drive/memory stick/USB stick Uses Can store several GBs of data and use solid state o Blu-ray disks are used in home video consoles technology o Used for storing and playing back films Connected to a computer through USB port and power o PCs can use this technology for data storage or backing to operate drawn from host computer up hard drives Some expensive software increasingly uses these storage o Camcorders can use this media to store film footage methods as a form of security Advantage Uses o Very large storage capacity o Used to transport files between computers o Data transfer rate is very fast o Used as a security device – a dongle – to prevent o Data access speed is faster than with other optical software piracy media Advantage Disadvantage o Very compact and portable media o Disks are relatively expensive o Very robust o Blu-ray disks still have encryption problems Disadvantage o Not possible to write protect the data and files 3.3 Solid State Backing Storage o Small physical size and are easy to lose. Solid state systems control the movement of electrons o Lower storage capacity than hard disk within a microchip: if the transistor conducts a current, this is equivalent to a 1, otherwise it is a 0 4. NETWORKS & THE EFFECTS OF USING THEM Have no moving parts, consume much less power and are extremely robust 4.1 Routers Used primarily as removable storage devices and are A device that enables data to be sent between different collectively known as flash memory types of networks Solid State Drives Commonly used to connect computers and other Supports reading/writing data & maintains stored data in network capable devices to the internet a permanent state even without power They can be connected to through cables or wirelessly Functions much like a hard drive but different tech PAGE 19 OF 57  CIE IGCSE INFO. COMM. TECH. //0417 Function Hubs Makes decisions on messages being passed between the They are devices that can have multiple devices networks connected to them Reads information about the message and decides Main task is to receive data from different ports and where the message should go and the best route for it to send it to each device get there The information will be received to the device whether Formats the messages making it suitable for the new its relevant, or not network Bridges How it Works It connects 2 different types of networks together e.g. a To send data to a specific device, a router needs a bus and star network something like an address It can only connect networks that use the same way for Internet Protocol Address: a unique number assigned to handling messages all computers and devices connected to the internet They do this by changing the form of message to suite which can determine its exact physical location the different type of network A router can use this IP to send data from the internet to Switches the exact device that requested it More efficient than hubs in distributing data Storing IP Addresses: Each device has an access control media address MAC o Routers store IP addresses in a routing table which identifies it uniquely o Routing tables list all the different routes to other MAC Address: a number unique to each device networks connected to the network (like fingerprints) o Routing table determines best route for data Data sent will have a mac address which tells the source Sending Data between Devices and receiving device Routers can also send ‘packets’ of data between devices Modems on different networks It stands for modulator demodulator. Each packet contains the data itself and the IP address of Converts computer’s digital signals (modulates it) into the device being sent to analogue for transmission through telephone lines Occurs globally using multiple routers & re-routing until Reverse this process- analogue signal from a telephone the data reaches its intended IP address line into digital for a computer to process the data (demodulates it) 4.2 Common Network Devices The main use it to connect to computer networks over Network Interface Cards long distances using existing telephone lines Used to connect individual computers/devices to a Types of Modems: network Dial-up modems: operate at 60 kilobits/sec NICs come in two distinct types: o slow compared to modern standards o Wired: cards that have ports which allow network Asymmetric: faster at downloading than uploading cables to be plugged in directly o (ADSL) asymmetric digital subscriber line modems o Wireless: cards that connect to networks using Wi-Fi operate at 11,000 kilobits/sec signals o Don’t tie up line while accessing internet, which allows simultaneous internet access and usage of telephone Cable modems: allow cable TV users to receive TV signals as well as internet access PAGE 20 OF 57  CIE IGCSE INFO. 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TECH. //0417 4.5 Web Browser 4.3 Wi-Fi & Bluetooth Software used to retrieve, present & traverse the World Wi-Fi Wide Web Any system which allows you to connect to a network or World Wide Web: system of interlinked hypertext computer through wireless communication documents accessed via the Internet Examples: HTTP Proxy Server o WLANs Type of server that acts as a buffer between a WAN and o PDAs a LAN o Laptop computers Retrieves web pages and passes them onto the o Peripheral devices such as printers computer that made a request Wi-Fi Hotspots Stores any page retrieved on the server, which means o Wi-Fi systems rely on AP (radio frequency technology) that when a different computer requests the same page to enable the device to receive and send signals it would be available o Wi-Fi hotspots are places where you can access Wi-Fi Speeds up the browsing process (free or paid) Websites o Hotspots are found in public places like Airports, Web is made up of millions of websites and web pages hotels, and cafés Web pages are documents on a computer screen o War driving: The act of driving and searching for containing various multimedia and text, pictures unsecured Wi-Fi hotspots A website consists of many of these pages linked o This gives a risk to the Wi-Fi system together Bluetooth Uniform Resource Locator (URL) Bluetooth is an example of wireless personal area Web browsers use URLs to retrieve files networking (WPAN) technology They are multiple ways of locating on the internet Spread spectrum transmission (radio waves) is used to Standard form: 4 numbers e.g. 194.106.220.19 provide wireless links between to devices such as mobile phones and allow connection to the internet Alphanumeric form: A small home network can be created with this system protcol://web address/path/filename o Where; Protocol is usually http Uses: o Site address consists of: computer name, domain o Transfer photos from camera to mobile phone name, domain type, and country code o Wirelessly connect different external devices o Path is the web page 4.4 Accessing the Internet o Filename is the item on the page User can access by web browser 4.6 Email TYPE OF DESCRIPTION A method for sending text and attachments from one ACCESS computer to another over a network DIAL UP Slowest type (60kbps) Advantages INTERNET Telephone line gets tied up while a dial up o Speed of sending and receiving replies is quick ACCESS modem is in operation o Low cost (no stamps, paper etc.) o Not needing to leave home to send the mail CABLE Disadvantages Local cable television operators give user INTERNET access through cable networks o Possibility of virus threats and hacking ACCESS o Need for the email address to be correct INTERNET Fastest download speed connections (at ACCESS VIA DSL o Inability to send bulky objects via emails least 11000kbps) PAGE 21 OF 57  CIE IGCSE INFO. 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TECH. //0417 4.7 Internet Service Provider (ISP) One of the hubs or switches will usually be connected to These are companies that provide users with access to a router/modem to allow LAN to connect to the internet the internet In doing so it then becomes part of a wide area network Provider in return for these services is charged a monthly Advantages or annual fee o The sharing of resources After paying this fee, a username and password are o Communication between users issued which can be used to connect to the internet o Network administrator can control and monitor all aspects of the network 4.8 Common Network Environments Disadvantages Internet o Easier spread of viruses throughout the whole network A worldwide collection of networks and computers that o Development of printer queues have joined together o Slower access to external networks e.g. internet Uses of the Internet: o Increased security risk o Web Browsing o If main server breaks down, usually the networks will o Email no longer function o File Sharing Wireless LANs (WLANs) o Entertainment Do not involve any wiring or cabling o Video Conferencing Provide wireless network connection overs a short o Online Banking distance o Advertising & Blogging They use radio or infrared signal's instead of cables o Social Media Devices known as Access Points (APs) are used for a Intranet larger range Like the internet but only accessible to specific users APs usually use spread spectrum technology (larger Basically, a private internet where outsiders cannot range) connect to it Advantages Uses of an Intranet: o All computers can access the same services and o Web Browsing resources o Email o No cabling is involved o File Sharing o The system is more flexible o Schools: share information and learning resources o Adding new computers and devices is very easy with students o Cost is reduced, and safety is improved o Businesses: share private information within a large Disadvantages company securely o Security is an issue Comparing Internet & Intranet o Problems and interference can affect the signal INTERNET INTRANET o The data transfer is slow than in the wired LAN Phrase International Network Internal Restricted Access Wide Area Networks (WAN) Origin Network WAN is formed by several LANs being connected through Purpose Globally share data Privately share data a router or a modem Audience Wide range of people Specific company or Some companies set up Private WANs, it is expensive organisation however it comes with a more enhanced security Access Anywhere if you are Only from within the connected company It is common to use an Internet service provider (ISP) for Local Area Networks (LAN) connections to the internet and communicate via this Not over a large geographical area (e.g. in one building) network system Typical LAN will consist of several computers and devices Additional hardware is needed for a WAN: Routers, Devices and computers will be connected to hubs or modems and proxy servers switches PAGE 22 OF 57  CIE IGCSE INFO. 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TECH. //0417 4.9 Using Different Types of Computers to MOBILE PHONES Access the Internet ADVANTAGES DISADVANTAGES LAPTOP COMPUTERS Smallest most portable of Websites are often not ADVANTAGES DISADVANTAGES all devices fully displayed More portable than Less portable than People more likely to Small screen size makes desktops can access internet tablets/smartphones carry this wherever they viewing websites difficult in more locations Screens not as large as go Small keyboards make it Larger screen than tablets & desktop PCs may not appear Much easier to connect difficult to type smartphones which allows as clearly to internet on-the-go Allow children access to easier reading CPUs are not as powerful as internet anywhere; can Keyboards are bigger than those in desktops be dangerous those on tablets/smartphones 4.10 Network Security Issues Touchpads allows easy navigation even on slanted Connection to a network exposes a user to: surfaces o Hacking: Unauthorised access given to computer. DESKTOP COMPUTERS o Phishing: Phishing involves getting sensitive ADVANTAGES DISADVANTAGES information such as usernames, passwords, and credit Most websites are designed Not portable so are limited card detail, for malicious reasons, by mimicking a to be viewed on a desktop to use in one room reliable webpage on the network Have larger keyboards Require keyboard and o Pharming: Explained in section 8.2 making it easier to type on mouse as extra peripheral o Viruses: Explained in section 8.2 devices Screens are larger so giving Screen and Monitor Policing the Internet an easier and better viewing consume separate power. Currently, the internet has no boundaries experience Anything and everything can be put online Usually use wired internet Cannot usually connect to For Policing: connections which is more devices like Bluetooth o Prevent illegal material being posted stable/reliable than Wi-Fi speakers without external adapter o People can easily find info on how to become hackers or make bombs Robust Take up large desk space o Prevent children from accessing undesirable websites Good heat dissipation- large Bulky to carry around body. o Could reduce the amount of incorrect information Against Policing: TABLET COMPUTERS o Material already available in other sources i.e. books ADVANTAGES DISADVANTAGES o Very expensive Smaller & lighter than Larger & less portable o Users would have to fund desktops & laptops than smartphones o Difficult to enforce rules making it easier to carry Uses Wi-Fi to connect to o Against freedom of information Larger screen than the internet which is less o Laws already exist to deal with perpetrators smartphones reliable than wired Inappropriate Websites On-screen keyboards Screens are smaller than Risk of finding undesirable websites larger than those on those on laptops & Risk of doubtful websites which are not genuine smartphones desktops They could lead to problems such as undesirable web On-screen keyboard is links, security risks not easy to type on PAGE 23 OF 57  CIE IGCSE INFO. COMM. TECH. //0417 4.11 Password Interception Face Recognition: Verifies the face of the person Spyware attempting to access the data using a face recognition Spyware is software that gathers user information algorithm and identifies facial features by extracting through their network connections without them being landmarks, or features, from an image of the subject's face. aware that this is happening Fingerprint Scanning: Scans the pattern on fingers and Once spyware is installed, it monitors all key presses and verifies it against a stored database of authenticated transmits the information back to the person who sent fingerprints using pattern-matching software to allow out the spyware access to a user. This software can install other spyware software, read cookies and personal information, and change the 4.13 Data Protection Act default home page or web browser Failure to abide to rules can lead to fines or Anti-spyware can be used to search out this software imprisonment and correct the corruption Rules (SAREF DES SAS) Weak & Strong Passwords 1. Data must be Fairly and lawfully processed Strong passwords: A random mix of alphabets 2. Data can only be processed for the Stated purpose (uppercase and lowercase), numbers, and keyboard 3. Data must be Adequate, Relevant and not Excessive symbols (@, %, ^ etc.) 4. Data must be Accurate Weak passwords: Easy to guess, e.g. users name or 5. Data must not be kept longer than necessary (Short date of birth or 1234556, etc. time) Frequent password changes can help reduce the chances 6. Data must be processed in accordance with the data of password interception too Subject’s right Passwords must not be shared, their strength is then of 7. Data must be kept Secure little use. 8. Data must not be transferred to another country unless