ICT Y9 - Term 2
The ICT Exam for Term 2 will consist of material from both the first and second term.
Material from the First Term will consist of notes associated with the study guide provided
by Mr Kodjo. The Second Term will consist of a thorough debrief of the unit “Big Data
modelling and analysis: Databases and Spreadsheets.”
Unit 9.2 - Design Your Own Network: Shape and Size
➢ Terms and Definitions
World Wide Web : The World Wide Web (WWW) is a network of online content that is
formatted in HTML and accessed via HTTP.
Web Browser : A web browser is a software program that allows a user to locate, access,
and display web pages.
Search Engine : A search engine is a software program that helps people find the
information they are looking for online using keywords or phrases.
Website : A website is a set of data and information about a particular subject which is
available on the internet.
Web server : A web server is a server that hosts and delivers website content efficiently.
➢ World Wide Web compared with the Internet
INTERNET WORLD WIDE WEB
A global system of interconnected Online content that is formatted in
computer network that use the TCP/IP HTML and accessed via HTTP protocol.
protocol to link devices worldwide
A massive interconnection of computer Service provided by the internet.
networks around the world.
Uses TCP/IP Uses HTTP
➢ Advantages and disadvantages of a computer network
Advantages Disadvantages
- performance enhancement - performance enhancement
- resource sharing - resource sharing
- increasing storage - increasing storage
-improved communication -improved communication
➢ Network topologies: Definition-Advantages and disadvantages
- In a Bus topology, devices share a cable with terminators to prevent signal reflection.
- In a Ring topology, devices connect in a ring, enabling unidirectional data flow.
- In a Star topology, devices connect to a central switch, enabling direct data transmission.
Type Of Topology Advantages Disadvantages
Bus Topology ● Easy to install. ● Main cable fails, network
● They are cheap as they don't stops working.
need a lot of cable. ● Network gets larger,
performance weakens.
● Visibility of devices poses
security risk.
Ring Topology ● Data flows one way which ● If main cable fails the
reduces chance of collision of network stops working
data
● Data can be transferred quickly
despite the number of devices
on it
Star Topology ● Each device is connected ● If main switch fails
separately. network will stop working
● Very dependable as rest of ● Expensive to install
network will continue to work if ethernet cabling
cable or device fails.
● Network performance is good
as the switch directs data to
the correct destination.
● easy to add new devices to the
network, as they can be
attached directly to the switch
➢ Network hardware: Functions
Router: A Router is a hardware device that connects networks together.
Firewall: A Firewall is a piece of Network Hardware that restricts the network traffic
entering and exiting the network.
Switch: A Network Switch is a switch that connects devices together to form a wired
network.
Server: A Server is a powerful computer that offers a range of services to a network.
● File Servers share and store data efficiently.
● Print Servers manage and coordinate printing tasks efficiently.
● Mail Servers handle and distribute emails securely.
● Web Servers host and deliver website content efficiently.
Network Interface Card: A Network Interface Card serves as the essential component to
connecting to a network.
Wireless Access Point: A WAP which stands for Wireless Access Point is a device that
allows wireless connection to the internet.
Ethernet: An Ethernet cable is a cord that runs from a router, modem, or network switch to
your computer, giving your device access to the local area network (LAN)
All-in-one devices: An all-in-one device is a PC that integrates all the components into a
single unit
➢ Network Protocols
Protocol: An agreed set of rules that computers follow to communicate over a network
TCP/IP: Transmission Control Protocol/Internet Protocol or TCP/IP is a protocol for
transferring data between devices.
HTTP: Hypertext Transfer Protocol is a Protocol used for communicating with web servers.
HTTPS: Hypertext Transfer Protocol Secure is a Protocol used for communicating between
web servers, with added encryption to improve security.
IP Address: Unique number assigned to a computer on a network.
Domain Name: Part of a URL that specifies the location on the internet
➢ Data packets and their components
Data Packet: Small unit of data that is packaged to be sent across a network
Components of a Data Packet:
Sender IP Address Receiver IP Address Packet Number
83.23.55.31 54.211.90.1 5/340
Data
011001101101101111011010110011011011011110110101100110110110111101101011001101101101111
011010110011011011011110110101100110110110111101101011001101101101
Receiver IP Address:
This needs to be included in PAcket number:
Sender IP Address: case of a ‘dropped packet’, This is included so that
The packet needs to which means a packet that the receiving device can
include this so that did not reach its destination. reassemble the jackets in
devices on the network If this is the case, the the correct order. It also
know where to forward receiver can request that helps the receiving device
the packet to. the packet is sent again. to understand if there are
any packets missing
➢ Parity checking, parity bits, and parity bytes conversion
Parity-Checking: Parity-Checking is a type of error check that ensures data has been
transmitted correctly.
Parity Bit: A parity bit is a bit added to a byte to make the total number of 1 bits either even
or odd. A parity bit ensures data has been transmitted correctly.
Dataset: A collection of related information that a computer can manipulate.
➢ Network security concerns and solutions
Firewall: A firewall is a special type of network hardware that examines the incoming and
outgoing network traffic to check for security risks and blocks suspicious activity. They
protect datasets by blocking access to the data from outside the network, or from specific
parts of the network.
User Access Controls: User Access Controls enablenetwork managers to allow some users
access to the datasets, but not others. For example, this could be helpful in a school by
allowing teachers to access datasets about student progress etc. Letting students access
this information wouldn’t be smart as it could be misused.
Password Policies: -Letters, numbers and symbols
-Be not longer than 10 characters
-not contain the user’s name
-no date
-Change regularly
Brute-force attack: A Brute-force attack is a type of unauthorised access to a computer
system that uses a large dictionary to try to multiple password combinations until
successful.
Biometric Security: Security method that identifies people using a physical attribute.
Two-factor authentication: A method of signing into a system that requires two types of
authentication.
Encryption: Converting information into a scrambled form, so that it cannot be understood
if it is intercepted.
Plaintext: Text that hasn’t been encrypted and can be read if intercepted.
Machine Learning: The ability of a computer system to learn over time
➢ Accessing the command line (MS-DOS)
1) Type “Run” into the start menu
2) When Run appears type in cmd then Enter
3) Then type in “ md (your name) depends on what you want to call the folder.
4) Type in “dir” then Enter
5) Type in “cd”
6) Type in md then the names of the files you want (md frog tshirt jog pen yemen)
7) To check the files type in dir
8) To check your files in file explorer, enter file explorer, then click “This PC”
9) Click “Local Disk (C:)” and select “Users” Folder
10) Then Manage to choose the folder your files are in (maybe HP)
Command Line: A way of using an operating system that is navigated by typing commands
Operating system: Software that manages all the computer hardware and software.
GUI: A Graphic User Interface is a way of using software that is navigated by pointing and
clicking on graphics on a screen,
Unit 9.5 - Big Data modelling and analysis: Databases and Spreadsheets
➢ Terms and Definitions
Database: An application that organises data for storing, processing and accessing
electronically,
Spreadsheet: Application that uses rows and columns to organise data and carry out
calculations using that data.
Big Data: Datasets that are too large or complex for traditional data-processing
applications, e.g. databases or spreadsheets, to process.
Big Data Analysis: The analysis of sets of data known as BIg Data.
Table: Set of data that is set out in a column and row structure.
Flat-file database: Database that stores all data using one table.
Data Redundancy: When data is unnecessarily repeated in a database. Data redundancy
can lead to a higher chance of data-entry errors.
Data-entry error: An error that occurs when data is being entered into a database.
Relational Database: A database that stores data using two or more tables.
Entity: Person, place, or object represented in a relational database.
Attribute: Heading for organising data in relational databases.
Primary Key: FIeld in a database table that provides a unique identifier for a record/entity
Foreign Key: When the primary key from one table appears in another table to establish a
link between two entities.
Entity Relationship Diagram (ERD): A diagram that illustrates the relationships between
two entities in a relational database.
Data Dictionary; A table that represents the structure of a database table at the design
stage of developing a database. Often contains details, e.g. data type, field length, etc.
Validation: Automatic checks applied to individual fields in a database table to help reduce
the chance of error when adding data to the table.
Input Mask: A control added to a field in a database table to control the format of data
being added.
Query: A tool that allows users to search for data that meets specific criteria or rules.
(Know the types man, I ain’t typin all that :\)
Search Criterion: A data item used for comparison when carrying out a search.
Criteria; Set of rules that must be met.
➢ Feature of Big Data: the 5Vs
Data Type: Classification applied to a data item specifying which type of data that item
represents. (Images, video, audio, animation, text, GPS)
5Vs: The terms used to describe the concept of Big Data: Volume, Velocity, Veracity, Variety,
Value.
● Volume: Volume when referring to Big data is if the data is big enough to even be
considered data.
● Value: How useful the data is. Whether the organisation who has collected the data
is able to use the data for useful or beneficial means.
● Veracity: The accuracy and quality of the data.
● Variety: Data collected and stored in databases or spreadsheets tends to be
structured.
● Velocity: How quickly data is transferred.
Big Data Applications:
Application Example of Big Data use
Transportation Google Maps uses Big Data analytics to plan routes that are
efficient, helping drivers avoid routes affected by traffic and
improving fuel consumption.
Delivery companies UPS analyses vehicle telematics from cars and trucks along with
advanced algorithms to calculate the best routes, automatically
control engine idle time and predict when maintenance is
needed.
Mobile-phone Some mobile phone companies combine data from a number of
companies their customer-management, billing and social-media
applications to predict when a customer might want to leave the
organisation and go to another mobile phone company.
Medicine/Healthcare Search engines such as Google work closely with health providers
to track when users are inputting search terms related to, for
example, flu topics. Working together, the organisations can
predict which regions may experience outbreaks. Big Data
analysis can also help medical professionals to predict and
prevent some diseases.
Media Streaming Media streaming services such as Netflix analyse international
Services viewing habits before they create or buy programmes that will
appeal to their audience.
Advertising and Advertising companies often buy or gather huge quantities of
Marketing data to identify what consumers actually click on, search for and
'like' when they are online. This data is used to tailor advertising
campaigns more effectively.
Banking Banks make use of Big Data analytics in the speedy identification
of unusual account activity. This allows them quickly to flag
potential illegal use of their customers' bank details.
Meteorology Using data collected worldwide by satellites and other sensors,
Big Data analysis allows meteorologists to produce accurate
weather forecasts, predict natural weather-related disasters and
make predictions about the impact of issues such as global
warming.
➢ Pros and cons of Big Data in the following sectors
Application Pros Cons
Transportation - Improved traffic management - Privacy concerns related to
and route optimization. tracking individuals'
- Enhanced vehicle safety movements.
through predictive - Reliance on technology may
maintenance. lead to vulnerabilities.
Delivery Companies - Efficient route planning and - Dependency on technology
delivery optimization. may lead to disruptions.
- Improved inventory - Data breaches may
management. compromise customer
information.
Mobile-phone companies - Predictive maintenance for - Privacy concerns regarding
network infrastructure. user data collection.
- Enhanced customer - Potential misuse of customer
experience through data by third parties.
personalized services
Medicine/Healthcare - Predictive analytics for - Patient privacy concerns.
disease outbreak and - Ethical issues related to data
prevention. sharing and consent.
- Personalized medicine and
treatment plans.
Media Streaming Services - Personalized content - Potential invasion of user
recommendations. privacy.
- Enhanced user experience - Algorithmic bias in content
through data-driven insights. recommendations.
Advertising and Marketing - Targeted advertising based - Privacy concerns and
on consumer behavior. potential backlash from
- Improved ROI through consumers.
data-driven marketing - Ad fraud and manipulation of
strategies. data for malicious purposes.
Banking - Fraud detection and - Security concerns related to
prevention. financial data.
- Personalized financial - Ethical considerations
services based on customer regarding the use of customer
behavior. data.
Meteorology - Improved weather - Uncertainty in predicting
forecasting and disaster complex weather patterns.
preparedness. - Dependence on accurate and
- Early detection of extreme extensive data for reliable
weather events. predictions.
➢ Practical
Create a blank database and work on tables to create relationships between them. You will
also be asked to create queries and run them.
