Overview
This lecture reviews key internet concepts, network types, security threats, and digital safety practices from the termâs theory modules for Grade 12.
Internet and Network Concepts
- The internet is a global network connecting millions of computers.
- A Wide Area Network (WAN) spans multiple geographic areas (e.g., the internet, large corporate networks).
- An Internet Service Provider (ISP) gives access to the internet and related services (e.g., email, hosting).
- Internet connection choices depend on mobility, data needs, speed (upload/download), and whether it should be capped or uncapped.
- Bandwidth is the amount of data that can be transferred in a given time.
- Throttling limits speed; shaping prioritizes certain data types at specific times; unshaped connections have no restrictions.
- Wired connections: ADSL and fiber have advantages/disadvantagesâknow two of each.
- Hotspots are wireless access points, often provided by routers, allowing devices to connect to the internet.
Internet Connection Technologies
- 3G, 4G, and 5G are generations of mobile data tech, each faster than the last.
- Wi-Fi provides internet via local networks; cellular uses mobile networksâchoose based on scenario needs.
Internet Services and Usage
- VoIP (Voice over Internet Protocol) transmits voice/video over the internet (e.g., Skype, WhatsApp calls).
- Video conferencing needs both hardware (camera, mic, laptop) and good connectivity.
- Cloud computing uses online software and storage (e.g., Gmail, Google Drive), requiring internet access.
- File sharing is quick and easy online, but limited by file size and recipientâs internet access.
- Email has attachment size and recipient limits; compression software can help send larger files.
- FTP (File Transfer Protocol) is used for transferring files between computers.
- Grid computing combines distributed computers to solve large problems.
Digital Divide and Online Government Services
- Digital divide separates those with tech access from those without due to cost, location, or knowledge.
Computer Crime and Security
- Social engineering tricks users into revealing confidential info.
- Malware refers to malicious softwareâinclude viruses, worms, trojans, ransomware, spyware, adware, bots.
- Phishing tricks users into giving up info; pharming redirects users to fake sites.
- Spoofing forges email headers; clickjacking disguises the real destination of links.
- Ransomware locks files and demands payment, often in bitcoin.
- Bots are compromised computers remotely controlled.
- Crimes include cyber stalking, bullying, spam, cyber terrorism, identity theft, and bandwidth theft.
Protection and Good Practices
- Use and regularly update antivirus software for protection.
- Always verify secure sites (lock icon, https), create strong passwords, and stay informed about threats.
- Do not share personal info or click unknown links; avoid opening unknown attachments.
- Follow the "paranoid ABC": Assume nothing, Believe no one, Check everything.
Key Terms & Definitions
- Internet â global interconnected computer network.
- ISP â company providing internet access and online services.
- Bandwidth â maximum data transfer rate of a network.
- Throttling â intentional slowing of internet speed.
- Shaping â prioritizing certain internet traffic types.
- VoIP â transmission of voice via internet protocols.
- Cloud computing â accessing software/storage via the internet.
- Phishing â tricking users to obtain confidential info.
- Malware â software intended to harm a computer or network.
- Ransomware â malware that locks data, demanding payment for release.
Action Items / Next Steps
- Review definitions and know at least two pros/cons for ADSL, fiber, VoIP, and cloud computing.
- Revise malware types and their symptoms.
- Practice scenario-based questions on connection types and digital security.
- Prepare for a practical session with theory and past exam questions.