“A good network engineer doesn't just solve problems; they anticipate and prevent them.”

Network Models:

• OSI Model: The Open Systems Interconnection model has 7 layers—Physical, Data Link, Network, Transport, Session, Presentation, and Application. Each layer has specific functions and protocols.
• TCP/IP Model: A more practical model used in real-world networking, with 4 layers—Network Interface, Internet, Transport, and Application.

Network Types:

• LAN (Local Area Network): Connects devices within a limited area like a home or office.
• WAN (Wide Area Network): Covers larger geographic areas, like cities or countries.
• MAN (Metropolitan Area Network): Connects networks across a city or large campus.
• WLAN (Wireless LAN): A type of LAN that uses wireless technology.

Subnetting: Dividing an IP address space into smaller segments to manage and organize network addresses more effectively.

Routing and Switching:

• Routing: The process of forwarding data packets between networks.
• Switches: Devices that connect devices within a LAN and use MAC addresses to forward data.

Protocols:

• TCP (Transmission Control Protocol): Ensures reliable, ordered, and error-checked delivery of data.
• UDP (User Datagram Protocol): Provides a faster, connectionless communication method with no error recovery.
• HTTP/HTTPS: Protocols used for web traffic (HTTP is unsecured; HTTPS is secured)