Network fundamentals
✅ What are Network Fundamentals?
Network fundamentals are the basic building blocks and principles that explain how computers and devices connect, communicate, and share resources over a network (locally or over the Internet).
👉 Think of it as learning how computers "talk" to each other!
🛜 Why Networking is Important?
Share Resources (printers, files, internet).
Communicate (email, chat, video calls).
Access Information (websites, databases).
Centralized Management (corporate environments).
⚙️ Key Elements of Network Fundamentals:
1. What is a Network?
A network is a collection of connected devices (nodes) that share data. Example: Computers, phones, printers connected via Wi-Fi or cables.
2. Types of Networks:
LAN (Local Area Network)
Small area (Home, Office).
WAN (Wide Area Network)
Large, global (Internet).
MAN (Metropolitan Area Network)
City-wide (Campus Wi-Fi).
PAN (Personal Area Network)
Around a person (Bluetooth).
3. Networking Devices:
Router
Connects multiple networks, gives internet access.
Switch
Connects devices in a LAN and manages traffic.
Modem
Connects network to ISP (Internet Service Provider).
Access Point (AP)
Expands Wi-Fi coverage.
Firewall
Security system to block unwanted traffic.
4. IP Address & MAC Address:
IP Address
Logical address for identifying devices on a network.
192.168.1.2
MAC Address
Physical hardware address of a device.
00:1A:2B:3C:4D:5E
5. Network Protocols (Communication Rules):
TCP/IP
Core protocol for Internet & networks.
HTTP/HTTPS
Web browsing (secure via HTTPS).
FTP
File transfers.
SMTP/IMAP/POP3
Email communication.
DNS
Translates domain names to IP (e.g., google.com → 142.250.190.78).
DHCP
Assigns IP addresses automatically.
6. Ports and Services:
Ports are like doors for different services (email, web).
Example:
Port 80 = HTTP (Web)
Port 443 = HTTPS (Secure Web)
Port 25 = SMTP (Email)
7. Data Transmission Methods:
Wired (Ethernet)
Fast, stable, uses cables (LAN).
Wireless (Wi-Fi)
Uses radio waves for mobility.
Bluetooth
Short-range personal networking.
8. Network Topologies (How Devices Connect):
Star
All devices connected to a central switch/router.
Most home/office networks.
Bus
All devices share a single cable.
Early LAN setups.
Ring
Devices connected in a circle.
Some specialized networks.
Mesh
Every device connects to others.
Modern Wi-Fi mesh networks.
9. Bandwidth & Speed:
Bandwidth = Maximum data capacity (e.g., 100 Mbps).
Latency = Delay in data transmission.
Throughput = Actual speed achieved.
🔐 Basic Network Security Concepts:
Firewall
Blocks unauthorized access.
VPN
Encrypts connection, hides IP.
Antivirus & Anti-malware
Protects devices.
Encryption (HTTPS)
Secures data transmission.
Strong Passwords/WPA3
Protect Wi-Fi networks.
🧠 Basic Network Troubleshooting Tools:
Ping
Test connectivity to another device.
Traceroute (tracert)
Track path to a server.
ipconfig / ifconfig
Check IP and network config.
nslookup
Test DNS resolution.
✅ Example: How You Access a Website (Simple Flow):
You type www.google.com in a browser.
DNS converts domain name to IP address.
Your device connects to Google's server via router.
Google sends website data back to your browser.
🔑 Summary (In Simple Words):
Network
Group of devices sharing data.
Router & Switch
Manage connections.
IP & MAC Address
Device identifiers.
Protocols
Rules for communication (TCP/IP, HTTP).
Firewall & VPN
Security measures.
Last updated