Unit 06
🌐 Largest Unit · 50 Periods
Data Communication
& Networking
The most comprehensive unit in the ICT syllabus. Learn how signals travel across media, how MAC protocols manage access, how IP addresses and routers connect the world into the Internet, how TCP/UDP deliver data between applications, and how DNS, HTTP and security protocols make the web work. Covers competency levels 6.1–6.12.
📡 Analog & Digital Signals
🔌 Guided & Unguided Media
🔤 Manchester Encoding
☎️ PSTN & Modems
🔗 Network Topologies
🔁 Hubs & Switches
📛 MAC Addresses & Frames
🌍 ALOHA → Ethernet
🔢 IPv4 Addressing
✂️ Subnetting & CIDR
🔄 DHCP & IPv6
🗺️ Routers & Packet Switching
📬 UDP & TCP
🔌 Ports & Multiplexing
🌐 DNS
📄 HTTP
📚 OSI Model (7 Layers)
🔗 TCP/IP Model (4 Layers)
🔒 Encryption & Digital Signature
🛡️ Firewalls & Antivirus
📶 ISP & DSL/ADSL
🏠 NAT & Home Networks
📚 Competency Levels — Unit 06
COMPETENCY 6.1 · 4 PERIODS
Signals & Their Properties
Analog and digital signal types. Properties: amplitude, frequency, wavelength and phase. Propagation speed in a medium. Graphical representation.
COMPETENCY 6.2 · 4 PERIODS
Signal Transmission Media
Guided media: twisted pair, coaxial cable, fibre optics. Unguided: free space/wireless. Properties: latency, bandwidth, noise, attenuation and distortion.
COMPETENCY 6.3 · 4 PERIODS
Digital Data Encoding
Voltage level encoding, Manchester encoding, frequency and phase encoding. Synchronisation and clocks. Parity bit for error detection.
COMPETENCY 6.4 · 4 PERIODS
PSTN & Modems
Public Switched Telephone Network as analog voice carrier. Modulation, demodulation and how modems connect two computers via a PSTN line.
COMPETENCY 6.5 · 4 PERIODS
Network Topologies
Bus, star, ring and mesh topologies. All-to-all impracticality. Hubs vs. switches for simplifying wiring and comparing functionalities.
COMPETENCY 6.6 · 4 PERIODS
MAC Protocol & LAN
LAN, MAC addresses, frames as transmission units. ALOHA protocol and its evolution to Ethernet. Broadcasting vs. unicasting messages.
COMPETENCY 6.7 · 6 PERIODS
IP Addressing & Internet
Gateways between LANs, IPv4 addresses, subnetting, subnet masks, CIDR notation, private IPs, DHCP, IPv6 overview. Routing, routers and packet switching.
COMPETENCY 6.8 · 4 PERIODS
Transport Protocols
Process-to-process communication. Multiplexing via port numbers. UDP — properties and applications. TCP — properties, reliability and applications.
COMPETENCY 6.9 · 4 PERIODS
Internet Applications
DNS — hierarchical distributed naming, translating domain names to IP addresses. HTTP — GET request and response. Client-server model.
COMPETENCY 6.10 · 4 PERIODS
OSI & TCP/IP Models
TCP/IP 4-layer model vs. OSI 7-layer model. Functions of each layer. Data units: packets, frames and bits. Data flow through layers.
COMPETENCY 6.11 · 4 PERIODS
Network Security
Encryption and digital signatures using public/private key pairs. Threats: viruses, trojans, malware, phishing. Protection: firewalls, antivirus and good practices.
COMPETENCY 6.12 · 4 PERIODS
ISP & Home Networks
Role of ISPs. Dial-up modems and DSL/ADSL connections. Home LAN with private IPs. Network Address Translation (NAT) and proxy servers.
📊 OSI Model vs TCP/IP Model
OSI Model — 7 Layers
7ApplicationData
6PresentationData
5SessionData
4TransportSegment
3NetworkPacket
2Data LinkFrame
1PhysicalBits
TCP/IP Model — 4 Layers
4ApplicationData
3TransportSegment
2InternetPacket
1Host-to-NetworkFrame/Bits
📥 Unit 06 — Available Downloads
📄
Full Notes — Data Comm & Networking
PDF · 5.8 MB · 80 pages
📄
OSI vs TCP/IP Model Chart
PDF · 0.9 MB · 4 pages
📄
IP Addressing & Subnetting
PDF · 1.4 MB · 16 pages
📄
Network Topologies Guide
PDF · 1.1 MB · 10 pages
📄
TCP vs UDP Comparison
PDF · 0.7 MB · 6 pages
📄
Network Security Notes
PDF · 1.2 MB · 12 pages
📊
Slide Deck — Data Communication
PPTX · 7.5 MB · 58 slides
📄
DNS & HTTP Notes
PDF · 0.8 MB · 8 pages
📄
Revision Summary Card
PDF · 0.6 MB · 2 pages
📄
Past Paper Questions
PDF · 1.8 MB · 20 pages
🗜️
Complete Bundle — All Files
ZIP · 21.8 MB · All resources