IGCSE ICT NOTES

Chapter 6:
6.1: Communication
Communication Media
Communication media describes the tools and channels for the sharing of information between a
sender and a receiver
Communication media can be both electronic and physical

Newsletters
Periodic publications, often used to inform, educate, or entertain subscribers about specific topics
Usually distributed through email or as printed copies
Suitable for organizations, schools, and clubs to keep members up-to-date

Posters
Visual presentations that convey information or promote events or products
Combine text, images, and graphics to grab attention

Websites
Online platforms that provide information or services
Accessible through the internet using a web browser
Useful for businesses, educational institutions, and individuals to share information, sell products, or
offer services

Multimedia presentations
Digital presentations that combine various forms of media, such as text, images, audio, and video
Used in education, business, and entertainment to present information in a visually engaging way

Audio
Sound recordings, such as podcasts, music, and radio shows can be streamed or downloaded for
offline listening
They are suitable for providing information, entertainment, or educational content

Video
Moving images with or without sound are used for entertainment, education, or promotional
purposes
Can be streamed or downloaded for offline viewing
Typical platforms include YouTube, and social media websites

Media streaming

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Real-time transmission of audio and video files over the internet
Allows users to access content without downloading it to their devices
Popular services include Spotify, Netflix, and YouTube

E-Publications
Digital versions of printed materials, such as eBooks, eMagazines, and eNewspapers
It can be read on electronic devices, such as eReaders, tablets, and smartphones
Offer benefits like portability, searchability, and adjustable text size

Mobile Communication
Mobile communication involves transmitting information between people and devices using radio
waves
Smartphones use subscriber identity module (SIM) cards to link the devices to a network carrier,
allowing them to make phone calls and send messages
Smartphones include features such as:
Feature Description
SMS messaging - Quick communication
- Messages are stored on the device and can be
read at any time
- Use virtual keyboards and predictive text
Phone calls - Simple voice communication
- Requires cellular reception
Voice over internet protocol (VoIP) - Audio communication via the internet
- Requires extra apps installed on the devices
- Can make & receive calls via smartphone,
tablet and computers
Video Calls - Audio and video communication in real-time
- Internet connection is needed
- Requires a forward-facing camera
- Often includes additional features like screen
sharing and chat options.
Accessing the internet - Requires cellular reception to access on the
move
- Web pages are optimized for smartphone
access
- Automatically uses Wi-Fi when in range and
connected

6.2: Modelling Applications

Computer modelling
Computer modelling is using a computer to simulate a real-life system in order to be able to study
the behavior in different scenarios
The simulation uses a model to help predict how the system will work in unusual circumstances
Advantages of using Computer modelling Disadvantages of using Computer modelling

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 rather than humans rather than humans
- Simulations can run faster than real-life - Expensive to develop and set up advanced
processes models
- Reduces costs associated with human - Requires skilled personnel to design and
resources and physical testing operate
- Eliminates safety risks to human life - Models may oversimplify or fail to account for
- Can simulate scenarios that are too large or unpredictable real-world variables
too small for human involvement - Accuracy relies on the quality and quantity of
- Models can be reused and adapted for input data because of data dependency
different scenarios - Over-reliance on models may lead to ignoring
human intuition and judgment

Modelling Applications include:

Application Description
Personal finance - Use of a spreadsheet to test 'what if' scenarios
- Using spreadsheet functionality to change values and see what impact is made
e.g. the financial impact on a family if household income is to go down
Bridge and - Architects will use 3D computer models of bridges and buildings so that many
building design scenarios can be tested
- In bridge design:
o How much traffic can the bridge take
o The effects of natural vibrations
o The effects of different weather conditions
o What impact on structural integrity would an accident cause
- In building design:
o Simulating fire evacuation protocols
o The effects of different weather conditions
o What impact on structural integrity would a fire cause
Flood water - Computer models allow risk assessments to be made of high-risk flooding areas
management
- Using models and changing variables allows for the design of automated flood
defence systems
- Variables would include:
o different rivers and sea inlets
o time of day
o previous flood behaviors
o possible obstructions etc.
- An automated system allows for:
o Real-time monitoring
o Faster response to changing conditions e.g. advance warning
to people

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 Traffic - Computer models allow users to see the effect of traffic and accidents on major
management road networks
- The data collected can be used to optimize the traffic light times at different
junctions
- Data collected could include:
o Time of day
o Number of vehicles passing the junction from all directions
o Factors that affect the flow of traffic e.g. pedestrians crossing,
accidents etc.
- After successful modelling has been completed, optimized systems can be built
and installed
Weather - Sensors are used to collect data and send it to a central computer
forecasting
- Data collected could include:
o Air pressure
o Wind speed
o Air temperature
o Humidity
- The computer model can then be used to predict weather patterns for the next
few days
- Actual weather is compared to the modelled data to check for accuracy and
identify any areas in the model to modify

6.3: Computer controlled systems

Computer controlled systems
A computer-controlled system uses computers and software to control, monitor, and manage
processes, machines, or devices
The effectiveness of computer-controlled systems depends on the quality of software, hardware, and
input data
Advantages of using computer-controlled Disadvantages of using computer-controlled
systems rather than humans systems rather than humans
- Consistency - Initial Cost
- Speed - Maintenance
- Cost-efficiency - Human unemployment
- Eliminates human safety-risks - Dependence on Technology
- 24/7 Operation - Decisions made may lack moral considerations
Robotics is the principle of a robot carrying out a task by following a precise set of programmed
instructions

Technology What It Is How It Works Advantages Disadvantages

Robotics in Robots used for Sensors detect - Increased - High costs
Manufacturing tasks like assembly, part positions efficiency
welding, painting, Processors analyze
- Limited
and speed adaptability
and packaging in data and decide
factories - High to new tasks
actions
precision
Actuators perform
tasks with - Safety

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 (handles
precision dangerous
tasks)
Production Line Automated Sensors track - Faster - High costs
Control systems control materials, production
material flow on processors adjust
- Downtime if
production lines production speed
- Consistent the system
output malfunctions
and alignment,
actuators control - Cost-
machines to effective
perform tasks. (reduces
labour costs)
Autonomous
Vehicles Sensors detect - Reduced - Expensive
surroundings (e.g., accidents technology
Vehicles that drive obstacles, road (human - Vulnerable to
themselves using conditions) error) hacking and
sensors, cameras, Processors make - Convenience technical
and AI. decisions (steering, (no driver failures
braking) needed) - Ethical
Actuators act. - Efficient concerns in
routing emergencies

6.4: School management systems

School management systems
A school management system is a software solution designed to centralize and streamline school
administrative tasks
Data is stored centrally to improve efficiency

Advantages of using School management Disadvantages of using School management

systems systems
- Improved communication between teachers, - High Cost
students, and parents - Transition can be time consuming and complex
- Centralized access to information and - Training is required
resources
- Dependent on technology
- Information is more up-to-date
- Data security concerns
- Information can be obtained quickly in an
emergency
- Patterns of absence can be found quickly which
helps tackle truancy/lateness

Processes that can be included in a school management system include:

 Registration and attendance
 Recording learner performance
 Computer aided learning (CAL)

Registration & attendance

Traditional ways of recording attendance and registration involve a teacher manually inputting data
The use of IT systems makes other methods possible. Eg: magnetic strip cards and/or biometrics

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Recording learner performance
Using IT systems gives teachers a lot of information which can be analyzed to identify a student’s
class and individual strengths, and areas for development
Data can be used to inform teaching strategies
Data can be used to provide individual progress reports
Data can be used to critically monitor class/teacher performance

Computer aided learning (CAL)

The use of computer aided learning is designed to enhance and not replace traditional classroom
teaching
CAL allows students to work on individual development areas
CAL can provide interactive revision resources to aid exam performance

6.5: Booking systems

Online booking systems
An online booking system is a computer system that allows customers to purchases tickets for events
online
Advantages of Online booking systems Disadvantages of online booking systems
- Convenience and accessibility (24/7 booking) - Potential for technical issues
- Reduces physical queues - Possible security and privacy concerns
- Instant confirmation and ticketing - Internet connected devices are required
- Can compare prices and options - Impersonal and less tailored customer service
- Faster to change/cancel tickets - Staff may lose their job
- Staff are freed up to do other things
- Reduced paper usage (for tickets etc)

Examples of industries that make use of these systems include:

 Travel - booking flights, hotels and package holidays
 Concert - Reserving tickets for live music events
 Cinemas - Booking cinema tickets, allowing customers to pick a seat
 Sporting events - Purchasing tickets to sporting events, choosing their view

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 Type of online Characteristics Uses Advantages Disadvantages
booking system
Travel industry - Real-time - Flight Bookings: - Bookings - Potential for
availability Reserve flights, available technical
- Seat choose seats, 24/7 issues
selection and manage - Reduces - Possible
schedules physical security and
- Payment
integration
- Hotel queues privacy
Reservations: - Immediate concerns
- Instant Book
confirmation booking - Requires
accommodation confirmatio stable
/ e-ticket s and amenities
generation n internet

- Customizable - Flexible to - Hidden fees

options modify or - Overbookin
cancel g or
- Multidevice
accessibility
- Personalized duplicate
suggestions reservations
- User
accounts
- Reduces - Limited for
paper usage special
(e-tickets) requests
Concerts - Real-time - Purchase - Bookings - Potential for
availability of concert tickets available technical
tickets - Can select seats 24/7 issues
- Seat - Book tickets for - Reduces - Possible
selection festivals and live physical security and
- Payment events queues privacy
integration - Immediate concerns

- Instant booking - Requires

confirmation confirmatio stable
/ e-ticket n internet
generation - Reduces - Hidden fees
- Multidevice paper usage - Risk of
accessibility (e-tickets) overbooking
Cinemas - Real-time - Book movie - Bookings - Potential for
availability of tickets available technical
tickets - Can select 24/7 issues
- Seat showtimes and - Reduces - Possible
selection seats physical security and
- Payment - Access queues privacy
integration upcoming movie - Immediate concerns

- Instant schedules booking - Requires

confirmation confirmatio stable
/ e-ticket n internet
generation - Reduces - Hidden fees
- Multidevice paper usage - Limited
accessibility (e-tickets) support for
special
queries

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 Sporting events - Real-time - Book sporting - Bookings - Potential for
availability of events tickets available technical
tickets - Can select seats 24/7 issues
- Seat - Purchase VIP or - Reduces - Possible
selection general physical security and
- Payment admission queues privacy
integration tickets - Immediate concerns

- Instant booking - Requires

confirmation confirmatio stable
/ e-ticket n internet
generation - Reduces - Hidden fees
- Multidevice paper usage - Risk of
accessibility (e-tickets) overbooking
- Access to
exclusive
offers

6.6: Banking applications

Banking applications
An Automatic Teller Machine (ATM) is used in the banking industry to provide customers with
convenient access to financial transactions 24/7
Advantages of ATMs Disadvantages of ATMs
- Convenient access to banking services - Technical issues and machine downtime
- Available 24/7 - Risk of physical and digital theft/fraud
- Reduced waiting time - Some banks charge for using ATMs
- Global access to funds - Cash withdrawal limits
- Limited services compared to bank branches

Characteristics and uses of ATMs:

 Withdrawing cash: Obtain money from a bank account
 Depositing cash or cheques: Add funds to a bank account
 Checking account balance: View the current balance of a bank account
 Mini statements: Obtain a summary of recent transactions
 Bill paying: Settle utility bills and other payments
 Money transfers: Sending funds to another bank account

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Electronic Funds Transfer (EFT)
Electronic funds transfer (EFT) is a system that allows money transfer instructions to be sent directly
to a bank’s computer system. No actual money is transferred; the whole system relies on electronic
transfer of money between accounts. When an EFT instruction is received, the computer system
automatically transfers the specified amount from one account to another.
EFT is primarily used for:
o Salary deposits
o Bill payments
o Online purchases

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 Advantages of using EFT Disadvantages of using EFT
- Fast and efficient - Technical issues
- Reduces paperwork - Risk of online fraud
- Lower transaction costs - Requires internet connection
- EFT transactions can be disputed for up to 60 - Requires immediate funds available
days
EFTPOS
Another example of EFT in use is when a credit/debit card is used to pay for a purchase in a store, the
payment is made using a system called electronic fund transfer at point-of-sale (EFTPOS)

Credit/debit card transactions

Their uses include
o Pay bills
o Purchase goods and services online or in store
o Withdraw cash at ATMs
Their characteristics include
o Electronic payment method
o Requires a physical card or card details
o Secured by PIN, chip, or OTP
o Supports contactless payments
o Instant transaction processing
In this example, suppose a customer goes into a restaurant to pay for a meal using a chip and PIN
card:

Advantages of Credit/Debit card transactions Disadvantages of Credit/Debit card transactions

- Fast and efficient - Dependency on card readers or internet
- Secure with fraud detection systems - Risk of fraud or theft
- Eliminates need for carrying cash - Hidden fees or interest charges for credit cards
- Enables international payments - Not all merchants accept cards

Cheques
Their uses include
o Pay bills
o Transfer funds between accounts
o Make payments for goods and services
o Issue payments for salaries or refunds

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Their characteristics include
o Written order directing a bank to pay
o Requires signature of account holder
o Can specify exact amounts
o Secure for large transactions
o Physical or digital format
Advantages of Cheques Disadvantages of Cheques
- Provides a record of transactions - Processing can be slow
- No need to carry large amounts of cash - Risk of fraud if lost or stolen
- Can be post-dated for future payments - relatively expensive payment method
- Can be traced if lost - Not widely accepted for smaller transactions

Internet banking
Internet banking is a secure online platform for accessing and controlling a person’s bank account
Internet banking can be accessed via the internet through a secure website or by using the bank's
official app on a smartphone
Its uses include
o Pays bills
o Transfers funds between accounts
o Account management
Its characteristics include
o Online platform for banking services
o Open 24/7
o Secure login with passwords/OTP
o Offers real-time account updates
o Supports mobile and desktop devices
Advantages of Internet Banking Disadvantages of Internet Banking
- Convenient 24/7 access - Low security of transactions
- Easy account management - More risk of fraud
- Reduced need for branch visits (saving time - Requires a reliable internet connection
and money) - Easier to make errors (typing in the wrong
- Interest rates may be better information)
- Easier to shop around for the best account - Physical cash can't be deposited/withdrawn

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6.7: Computers in medicine
Information systems in medicine
An information system is a purpose-built system designed to collect, store, process, distribute and
use information

Information Systems for Patient Records

Characteristics
1) Digital storage of medical history
2) Contains demographic data, diagnoses, treatments, and test results
3) Accessible to authorized personnel
4) Secured with encryption and user authentication
5) Supports interoperability (the ability of computer systems or software to exchange information) across
healthcare facilities
Uses
a) Tracks patient history for better diagnosis
b) Share medical information between specialists and hospitals
c) Research and analysis for public health improvement

Information Systems for Pharmacy Records

Characteristics
1) Digital storage of prescription details
2) Tracks drug inventory and availability
3) Integrated with patient records and doctor prescriptions
4) Secured with access control and encryption
Uses
a) Dispense medications accurately
b) Track patient medication history
c) Monitor prescriptions to prevent errors or misuse
d) Analyze prescription trends for public health insights

3D printers
Printing of prosthetics - Custom-made prosthetic limbs or body parts
- Can be tailored to a patient's specific needs
- Faster and more affordable than traditional
methods
Tissue engineering - 3D printing of living cells to create functional
tissues
- Can be used to repair or replace damaged
organs
- Can potentially reduce the need for organ
donations

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 Artificial blood vessels - 3D printed blood vessels made of
biodegradable materials
- Can be used in surgeries to replace damaged
vessels
- Allows for improved blood flow and faster
healing
Customized medicines - 3D printed pills with precise doses and drug
combinations
- Tailored to a patient's specific needs and
conditions
- Potential to improve medication adherence
and effectiveness

6.8: Expert systems

Expert systems
An expert system mimics human knowledge and experience and uses a combination of the two to
solve problems or answer questions
Characteristics
o Mimics human decision-making
o Uses a knowledge base and inference engine
o Provides explanations for decisions
o User-friendly interface for non-experts
Uses
o Mineral Prospecting: Helps find minerals
o Car engine fault diagnosis: Helps understand car faults
o Medical Diagnosis: Helps doctors identify diseases
o Chess games: Helps understand and analyze chess games
o Financial Planning: Makes future investment projections and helps users fully control their flow of
wealth
o Route Scheduling for delivery vehicles: Helps guide vehicles for optimal routes
o Plant and animal identification: Can recognize plants and animals
Purposes
o provide expert-level decision-making and advice
o To reduce dependency on human experts
o To ensure consistent and reliable outcomes
o To save time and resources by automating complex problem-solving tasks
Advantages of expert systems Disadvantages of expert systems
- Consistent results - Only as good as the data entered
- Faster responses - Responses can be cold and lack human
- Can store large amounts of data emotion

- Unbiased - Requires training to use correctly

An expert system is made of many parts that work together for the system to function including:

User Interface
This is the method by which the expert system interacts with the user

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It allows interactions through dialogue boxes; command prompts or other input methods
The questions being asked usually only have yes/no answers and are based on the responses to
previous questions
It can be in the form of text-based interfaces, graphical user interfaces (GUI), or even voice-based
systems

Inference Engine
This is the main processing element of the expert system
It gathers information from the user by asking a series of questions and applying responses where
necessary; each question being asked is based on the previous responses
The inference engine is the problem-solving part of the expert system, which makes use of inference
rules in the rules base
Because the knowledge base is a collection of objects and attributes, the inference engine attempts
to use information gathered from the user to find an object that matches (making use of the rules
base to find a match)

Knowledge Base
The knowledge base is the database of facts
It stores all the knowledge about an area of expertise obtained from a number of expert resources
The accuracy and comprehensiveness of the knowledge base determines how effective the expert
system is

Rules Base
This contains the inferential rules (IF-THEN statements) that the inference engine uses to process
knowledge
Inference rules are used by the inference engine to draw conclusions (the methods used closely
follow human reasoning)
They follow logical thinking

Explanation System
It tells the user the reasoning behind the expert system’s conclusions
Gives a percentage probability of the conclusion being accurate
For example, suppose the user was investigating a series of symptoms in a patient and the expert
system gave the diagnosis of mercury poisoning; the explanation system would explain its reasoning
with a statement such as ‘impaired vision, lack of coordination, weak muscles, slurred speech and
the patient used to work in a paint factory’.
The user could then probe deeper if necessary. The expert system will supply a conclusion and any
suggested actions to take; the important thing is it will also give the percentage probability of the
accuracy of its conclusions (for example, the following statement could be made: ‘Based on the
information given to me, the probability of finding oil bearing rocks in location 123AD21G is about
21%’).

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Expert System Components

Users input the data, using the user interface

Expert system compares the data with Knowledge base
The Inference Engine processes the data using IF-THEN rules from the Rules Base
Based on the inference, the system suggests a solution
The Explanation System shows how the system arrived at its decision
6.9: Computers in the retail industry
Computers in the retail industry
Characteristics of computers in the retail industry:
24/7 Operation
User-Friendly Interfaces
Integration with Other Systems
Security
Automation
Data Processing

Point of Sale (POS) is a computerized system used for sales transactions

It typically includes:
 A barcode scanner (to scan product prices)
 A receipt printer (to generate customer receipts)
 A cash drawer (for cash payments)
 A touchscreen monitor (for cashier interaction)
 A card reader/EFTPOS system (for card transactions)

Updating stock files automatically and ordering new stock automatically:

 Every barcode is already assigned to a product in a stock

 Each product record contains its price, stock level and a description
 When a barcode is matched with a record the information is transferred to the POS terminal
and the price is displayed on the screen
 The stock level is reduced by one
 If the current stock level falls below a minimum reorder stock level it triggers a restocking
process automatically
 When the supplier delivers stock, the system updates the inventory

Electronic Funds Transfer at the Point of Sale (EFTPOS)

EFTPOS terminals allow customers to pay using credit/debit cards or mobile wallets
Examples of EFTPOS include:
 Chip and Pin
 Contactless
 Near field communication devices (NFC)

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 Chip and Pin Contactless NFC
- Enhance security with two- - Allow for faster transactions - Facilitate payments through
factor authentication - Enable customers to tap smartphones and other
- Require customers to enter their card on the terminal devices
a personal identification - Increase convenience for
number (PIN) customers

1. Checking Validity of Cards

 The card is swiped, inserted, or tapped at the EFTPOS terminal.

 The system verifies card details (expiry date, card number, available funds) by contacting the
issuing bank
 The bank approves or declines the transaction

2. Use of Chip and PIN

 Chip:
o Cards have an embedded microchip for secure data storage
o Data is encrypted, making it difficult to clone
 PIN (Personal Identification Number):
o The customer enters a PIN to confirm the transaction
o The PIN is verified against records stored securely by the bank

3. Use of Contactless Cards

 Cards use RFID (Radio Frequency Identification) to enable tap-and-go payments.

 No PIN is required for small transactions (up to a certain limit)
 Data is transferred wirelessly between the card and the EFTPOS terminal.

4. Use of Near Field Communication (NFC) Payment

 Used for mobile payments (e.g., Apple Pay, Google Pay)
 The device communicates with the EFTPOS terminal over a very short range
 Requires two-factor authentication (e.g., fingerprint or face recognition)
 Uses tokenisation (turns your 16-digit card number into a different number stored on your
device, so your actual card information is never intercepted when you tap your phone)

5. Communication Between Supermarket Computer and Bank Computer

When a customer initiates a payment, the process involves the following steps:
 EFTPOS Terminal Sends Data to Supermarket Computer:
 The EFTPOS terminal captures the card details, payment amount, and
retailer information
 This data is encrypted and sent to the supermarket’s computer
 Supermarket Computer Contacts the Bank:
 A secure network sends payment authorization requests to the bank's
system
 Bank checks funds & card validity
 Bank approves/declines the payment
 EFTPOS updates transaction status & prints receipt

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Internet Shopping
Advantages of Internet Shopping Disadvantages of Internet Shopping
- Online shops are open 24/7 - Security issues
- A greater product market for consumers - Internet access is required
- No travel costs - Local independent retailers may lose out to
- Shops do not need as many physical staff huge multinational retail companies
members reducing congestions etc. - Money may accidently be transferred to
incorrect accounts

Internet shopping is the act of purchasing goods or services online; through a website or mobile
application

Characteristics of Internet Shopping

o Online stores accessible through web browsers
o Wide variety of products and services
o Convenient and often open 24/7
6.10: Recognition Systems
Recognition Systems
A recognition system is a way of using computer technology to automatically identify something

Optical Mark Recognition (OMR)’s

Optical Mark Recognition (OMR) detects marked areas on paper by using a special machine to read
the marks
Examples include:
 School registers
 Multiple-choice examination
 Barcodes
 QR codes
Advantages of OMRs Disadvantages of OMRs
- Fast data collection - Limited to predetermined responses
- Reduces manual entry errors - Sensitive to poor marking or smudging

Optical Character Recognition (OCR)s

Optical Character Recognition (OCR) converts printed or handwritten text into digital format
 Automated Number Plate Recognition (ANPR) uses OCR
o For example, reading number plates and controlled entry and exit at airport parking
 Useful for digitising documents
 Assists in searching and editing text
Advantages of ANPRs Disadvantages of ANPRs
- No staff required - Privacy concerns as number plates are
- Faster, no need to stop and take tickets etc. recorded

- Stops cars parking illegally, cannot enter - Number plates can be cloned
without authorization - Dirty or broken number plates cannot be read

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Radio Frequency Identification Devices (RFID)s
Radio Frequency Identification Devices (RFIDs) use radio waves to identify and track objects
RFID tags are made of a microchip and antenna and can be either:
 Passive (weaker) - uses energy from the reader
 Active (stronger) - has its own power source
Advantages of RFIDs Disadvantages of RFIDs
- Fast and automatic scanning – RFID tags can - Expensive – cost more than barcodes
be read without line-of-sight, unlike barcodes. - Signal interference – Metal objects and radio
- Can scan multiple items at once signals can disrupt RFID scanning
- More durable than barcodes – RFID tags last - Privacy concerns – RFID tags can be tracked
longer and are less likely to be damaged. without permission
- Better security – RFID tags can store more data - Limited range – Passive RFID tags have a short
and be encrypted. range compared to active tags

Tracking stock - Livestock tracking on a farm

- Location
- Medical data
- Active tags would be used due to the distance
involved
Passports - Passive chips in passports
- Read by a reader to decrypt data stored on the
chip
- Personal details
- Photo
- Fingerprints
Vehicles/automobiles - Track progress on assembly line
- Used on toll roads to automate payment and
raise barriers
- Entry and exit to carparks
Contactless Payments - The chip in the RFID tag is passive and emits a
low-powered radio wave when it comes into
contact with an RFID reader.
- An antenna is built into the card to allow a
connection with the contactless reader.
- The RFID reader picks up a signal from the chip
and this initiates the payment process

Near field communication (NFC)

Near field communication (NFC) is a subset of RFID which allows communication between two
devices in very close proximity
NFC can be either:
Passive - uses energy from the reader OR
Active - has its own power source
Smartphones use active NFC to allow contactless payments by tapping a smartphone on a reader

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Smartphones can also exchange data using NFC by tapping together (usually back-to-back)
Biometric Recognition
Biometric recognition uses unique human characteristics for identification
Types of biometric recognition systems
 Face: (scans facial features)
 Iris: (scans the coloured part of the eye)
 Retina: (scans blood vessels in the eye)
 Finger/Thumb: (scans fingerprints)
 Hand: (scans hand shape and palm structure)
 Voice: (analyses speech patterns)

6.11: Satellite Systems

Satellite Systems:
Global Positioning Systems (GPS)
Characteristics:
1) Satellites surrounding the Earth transmit signals to the surface, which contain information like
their position
2) They use atomic clocks because they need very accurate timings
3) Computers in a car need signals from at least 3 satellites to determine the car’s position
Uses:
a) Determining the exact location of vehicles
b) Determining the exact location of a device
c) Locating Packages
Pros:
i) Safer and more convenient than paper maps
ii) Can estimate the time of arrival
iii) Can give the most efficient route and avoid potential delays (such as heavy traffic, street
closures, etc.)
iv) Can give useful information such as the location of petrol stations
Cons:
(1) Maps can be out of date
(2) Road closures due to accidents or construction, can cause problems, unless the
system is very sophisticated
(3) If an incorrect start-point or end-point is keyed in, the system will give incorrect
information

Satellite Navigation (the device or system using GPS)

Characteristics:
1) Contains stored road maps; when this is combined with GPS information, it can display a live
position on a map and give instructions on how to reach destinations
a) Uses: Determining the exact location of cars
Pros:
i) Same as above
Cons:
(1) Same as above

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Geographic Information Systems (GIS)
Characteristics:
1) Computer system that allows users to map, model, and query large amounts of data according to
location
2) (GIS is a technology that is used to create, manage, analyse, and map all types of data. GIS
connects data to a map, integrating location data (where things are) with all types of descriptive
information (what things are like there))
Uses:
a) Performing complex analytical calculations and queries
b) Presentation of the results in the form of maps, tables or graphics (or a combination of all
three) so it is easy to understand
c) Geographers, scientists and engineers are able to see the data in several different ways in
order to see patterns and relationships
Pros:
i) Wide scale pattern identification
ii) Presentation of information in maps and graphics makes it easier to understand
Cons:
(1) Expensive
(2) Hard to learn
(3) Not user friendly; they need very complex command language interfaces to work
properly
(4) A lot of data is needed, increasing the chances of errors

Media Communication Systems (Satellite Television & Satellite Phone)

Characteristics:
1) Use artificial satellites to transmit signals over long distances
2) Communicate via radio waves or microwaves.
3) Signals are sent from the Earth to a satellite in space, which then transmits them back to Earth.
4) Can cover large areas and work in remote locations where traditional networks fail.
a) Uses: Used to send data across very long distances (because it is too expensive and
impractical to do so with wires) and there is a problem of signal degradation in wires
Pros:
i) Global coverage; can be used in very remote locations
ii) Cheaper, faster and safer than laying cables in difficult or treacherous terrain
iii) Relatively easy to expand the network
iv) High-quality transmission
Cons:
(1) Time delay, which causes what seems like an echo (this would also be a problem in
long distance fibre-optic communication)
(2) Weather interference can disrupt signals
(3) Expensive – Setting up satellite systems (e.g., satellite dishes, phones) can be costly.
(4) Satellite phones are bulky

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Chapter 7:
Overview
System: Hardware, software, users, procedures
System’s Life Cycle:
Analysis: Collect information about the existing system and its problems and what will be needed in
the new system
Design: Plan out the new system
Development and Testing: Make the new system and test it
Implementation: Implement the new system
Documentation: Documentation with information and instructions about the new system for both
developers and users
Evaluation: Evaluate the new system and how well it solves the problem with the old system

7.1 Analysis
Analysis of the current system
Analysis: Collect information about the existing system and what will be needed in the new system

Observation
Characteristics:
1) Watching personnel use the existing system to find out how it works and what is needed;
qualitative
Uses:
a) Broad analysis
Pros:
i) Overall view of the system
ii) Reliable data, the analyst sees the system naturally
iii) Relatively inexpensive, only requires the analyst
iv) The analyst can see what users think of the system
v) Users do not need to be distracted from their work
Cons:
(1) People are usually uncomfortable being watched
(2) Hawthorne Effect: People behave differently when watched. They may also behave
differently because they may interact with the system in a non-standard way

Interviews
Characteristics:
1) A one-to-one question-and-answer session between the analyst and the user; qualitative
Uses:
a) Deep and specific analysis
Pros:
i) It is easier to motivate the interviewee to be open and honest due to privacy
ii) More feedback can be asked for as required
iii) It is possible to modify questions as the interview proceeds (follow-up questions)
iv) Analyst can watch body language and facial expressions
Cons:

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 (1) Time consuming
(2) Expensive
(3) Interviewee cannot remain anonymous so they may hide information or not be
honest
(4) Interviewee may give answers they think the interviewer wants to hear
(5) Users may not have time for an interview

Questionnaires
Characteristics:
1) Distributing questionnaires to the system users
Uses:
a) Very broad analysis; can be quantitative or qualitative
Pros:
i) Very broad
ii) Little time needed; users can fill in the questionnaire whenever convenient
iii) Relatively inexpensive
iv) Anonymous, more likely for answers to be accurate
v) Quick analysis if in quantitative form
Cons:
(1) People may not do their questionnaires and return them
(2) Questions have to be generic and follow up questions are not possible; vague or
short answers cannot be clarified or expanded
(3) Users are anonymous, so they may exaggerate or be non-serious

Examination of Existing Documents

Characteristics:
1) The analyst looks at all the details and documents related to the system
Uses:
a) Direct analysis
Pros:
i) Allows information to be obtained which was not possible by any of the other methods
ii) The analyst can see for themselves how the current system operates
Cons:
(1) Time consuming
(2) Expensive
(3) Tells nothing about users’ opinions about the system

Record and analyze information about the current system

Information about the Current System Needed:
Inputs, Outputs, Processing
Problems

Information about the New System Needed:

User and Information Requirements

User Requirements:
Written by the analyst for business managers (customers)

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Easy for laymen to understand, because the business managers are not experts in IT
Helps business managers judge whether the new system meets their company’s needs
Describes what the business managers need the system to do, based on discussions between them
and the analyst

Information Requirements:
Information requirements refer to the data and information needed for the new system to effectively
support the business

System specification
Hardware and Software Requirements: Identify, and justify suitable hardware and software needed
for the new system

7.2 Design
Design:
File/Data Structures: How the files containing data will be structured
o Field Length: The maximum number of characters that may be stored
o Field Name: The name of the field
o Data Type: Alphanumeric, Text (Single Letter, Short Text, Long Text), Numeric (Integer,
Decimal, Currency, Date/Time), Boolean
o Coding of Data: A single character used to represent something larger, like M for male and F
for female

Validation Routines: The process where data entered into a computer is checked to see if it satisfies
certain criteria. Types include:
 Range Check: Checks if numeric data meets an inequality. eg: less than 5; or between 1 and
10
 Character Check: Checks if the data only has characters from a specific set of characters
 Length Check: Checks if the data meets maximum and/or minimum length requirements
 Type Check: Checks if the data is the right type (text, integer, boolean, etc)
 Format Check: Checks to see if the data input is in the correct format, like dd/mm/yyyy for
dates
 Presence Check: Checks if any data has been entered in a field
 Check Digit: An extra digit added to a number which has been calculated from the other
digits. It can detect three kinds of errors:
o If two digits have been swapped
o If a digit is incorrect
o If a digit is missing or if there is an extra digit

Input Formats:
Data Capture Forms: Forms used to input data into the system, they need to be carefully designed
so that the data entered will have the correct format. They can be paper or electronic-based:

Paper-Based:
 Clear heading

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  Clear fonts and text colours so that the form is easy to read
 Clear spaces for answers
 Sufficient space to write answers
 Text boxes, limits the amount of information collected
 Character boxes which allow one character only for data such as surnames, telephone
numbers, etc
 Formatted text boxes to allow for easy input of items such as dates
 Tick boxes, to make choices easier (such as gender – male or female)

Electronic Based:
 On-screen help when completing the form
 Text boxes, to capture key data clearly
 Drop-down/combo boxes, for limiting choices
 Radio buttons and tick boxes, for limiting choices and convenience
 Double entry boxes (with different verification rules) to check correctness of key data
 Automatic validation of data as it is entered, for efficiency and convenience
 Control buttons (such as next form, clear entry, save, etc.)

Output Formats:
Screen Layouts:
Screen Layouts: An output displayed on a screen or on paper mimicking a screen
 The size of all the output fields is correct, so it fits on the screen while also utilising the full
screen
 Any instructions/descriptions are clear
 Colours and fonts (size and type) make the output clear
 Avoiding large areas of blank space

Report Layouts
Report Layouts: An output in the form of a formatted table
 Should have a clear label to show what the report is about
 Should clearly show all the fields that were included in the search criteria

7.3 Development and Testing

Testing:
The Need for Testing:
 To make sure the file system is robust
 To ensure inputs lead to the correct outputs
 To check validation routines
 To ensure specialised hardware has been implemented correctly
 To ensure the system is user friendly

Testing:
Test Designs: How a system is to be tested

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  Data Structures: How to test that each field has a correct type of data (e.g. text, numbers,
dates) which can be accurately stored and retrieved
 File Structures: How to test that the file structures function correctly (i.e. data is stored in the
correct format and can be accurately retrieved)
 Input Formats: How to test that all data is entered into the system correctly (Makes sure the
format is exactly right e.g. DD-MMM-YY)
 Output Formats: How to test that screen outputs and reports are all in the correct format,
clear, complete and correctly match the input data
 Validation Routines: What data is needed to test to see if all the validation rules work

Test Strategies: The strategy used to test the system

 Each Module: Software is often in a modular form, with each module made by a separate
programmer or team of programmers. Each module can be tested separately.
 Each Function: Testing each function of the whole system, to see how well it meets its
purpose
 The Whole System: Even if each module functions individually, they may fail to work with
each other

Test Plan: The actual test to be performed on each module; it should have a list of all the
tests to be performed and should keep in mind test data and everything related to it
 Test Data: The data being used to test the system. There are multiple types:
o Normal: Input data that is acceptable; checks if the system will accept the data
o Abnormal: Input data that is not acceptable; checks if the system will not accept the
data
o Extreme: Input data that is at the limits of acceptability (e.g. 5 for ‘up to 5’); checks if
the system has a correct range
 Live: Live data is data from the old system used on the new system, it has known outcomes
(expected outcomes)
 Expected Outcomes: The outcomes that are desired when live data is input into the system
 Actual Outcomes: The outcomes that actually happen when live data is input into the system
 Remedial Action: Action taken when the actual outcomes do not match the expected
outcomes when live data is input into the system, to make the actual outcomes match the
expected outcomes

7.4 Implementation
Testing
Methods of Implementation:

1) Direct Changeover: The old system is stopped overnight and the new system is introduced
immediately
Uses:
a) Whenever a change needs to happen very quickly or be done very cheaply
Pros:
i) Fast implementation
ii) Cost-effective as only one system is in operation
Cons:

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 (1) High risk of failure
(2) No fallback (emergency plan)
(3) Users can't be trained on the new system

1) Parallel Running: The old and new systems are run together for some time before the new
system takes over
Uses:
a) A better method under normal circumstances
Pros:
i) Lower risk
ii) Fallback
iii) Users can be trained on the new system
iv) Easy comparison of systems
Cons:
(1) Slow
(2) Expensive

1) Pilot Running: The new system is introduced into one country/part-of-the-company etc and its
performance assessed before being introduced elsewhere in the country/company
Uses:
a) A safer approach
Pros:
i) Low risk as only trialled in one department/centre/branch/country
ii) Gives time for fine-tuning
iii) Staff have time to train with the new system
iv) Few errors as it's fully tested
Cons:
(1) Slow
(2) Potential locational compatibility issues
(3) No backup for the department/centre/branch using the new system

1) Phased Implementation: Only one part of the new system is introduced and, only when it
proves to work satisfactorily, is the next part introduced, and so on, until the old system is fully
replaced
Uses:
a) Very safe
Pros:
i) Reduced risk
ii) Easier to manage
Cons:
(1) Takes longer
(2) Potential compatibility issues for different phases working together

7.5 Documentation
Documentation

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Types of Documentation:

Technical Documentation: Detailed information on the system's inner workings and programming
for developers and IT staff
Characteristics:
 Purpose of the System/Program: Explanation of the system's intended function and goals
 Limitations of the System: Known constraints or issues with the system
 Program Listing: The code or scripts used in the system
 Program Language: The programming language used to develop the system
 Program Flowcharts/Algorithms: Visual representations or descriptions of the system's logic
and processes
 System Flowcharts: Visual representations of the interactions between system components
 Hardware and Software Requirements: Necessary equipment and software to run the system
 File Structures: Organisation and layout of the system's files and data
 List Of Variables: Collection of variables used within the system, including their names and
purposes
 Input Format: Structure and format for entering data into the system
 Output Format: Structure and format for presenting data generated by the system
 Sample Runs/Test Runs: Examples of system operation, including input and expected output
 Validation Routines: Techniques used to check and confirm the accuracy of data entered into
the system
 Uses: Used as a reference for developers and IT staff
 Purpose: Allows the system to be maintained, repaired, and updated

User Documentation: Instructions and guidance for end-users on how to operate the system
Characteristics:
 Purpose of the System: Explanation of the system's intended function and goals
 Limitations of the System: Known constraints or issues with the system
 Hardware and Software Requirements: Necessary equipment and software to run the system
 How To Load/ Run/Install Software
 How To Save a File
 How To Print Data
 How To Add Records
 How To Delete/Edit Records
 Input Format: Structure and format for entering data into the system
 Output Format: Structure and format for presenting data generated by the system
 Sample Runs: Examples of system operation, including input and expected output
 Error Messages: Explanations of system warnings and error notifications
 Error Handling: Steps to resolve issues and errors within the system
 Troubleshooting Guide/Helpline: Assistance for diagnosing and addressing common
problems
 Frequently Asked Questions: Answers to common user inquiries
 Glossary Of Terms: Definitions of key terms and concepts related to the system
 Uses: Used as a reference for users
 Purpose: Enables end-users to effectively use the system and overcome problems

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7.6 Evaluation
Evaluate a Solution:
 Efficiency of the Solution: See the efficiency in terms of resource usage, time, and cost
 The Ease of Use of the Solution: How user-friendly and accessible the solution is for its
intended audience; evaluate the users’ responses to the results of testing the system
 The Appropriateness of the Solution: How well it meets the intended purpose and original
task requirements

Compare the solution with the original task requirements

Identify any limitations and necessary improvements to the system
Evaluate the users’ responses to the results of testing the system

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