Understanding LANs and WANs

LANs (Local Area Networks)

• LANs cover small geographical areas, usually a single site.
• LAN hardware is owned by the organization using it.
• LANs can be wired (e.g., Ethernet cables) or wireless (e.g., Wi-Fi).
• Common in businesses, schools, and universities.
• Many homes have LANs to connect devices like PCs, tablets, smart TVs, and printers.

LAN Advantages

• Easier file sharing and collaboration among network users.
• Shared hardware like printers.
• Centralized software installation and updates.
• Inexpensive and easy communication (e.g., instant messaging).
• Centralized user account storage for device logins.

WANs (Wide Area Networks)

• WANs connect LANs across different geographic locations.
• Businesses with offices in multiple countries often use WANs.
• WANs typically involve hired infrastructure (e.g., communication lines) from telecommunication companies, which makes them more expensive than LANs.
• WAN connections can use fiber optic cables, copper telephone lines, satellite links, or radio links.
• The internet is a large WAN.

Network Components

• NIC (Network Interface Controller): Internal hardware for device connection to a network. Previously separate cards, now often built into motherboards.
• Switches: Connect devices on a LAN; receive data and forward it to the correct device based on its MAC address.
• Routers: Responsible for transmitting data between networks. Essential for internet connectivity, guiding data packets to their destination. Often combine multiple functions like switching and Wi-Fi access point (WAP) capabilities.

Wired Ethernet Connections

• Ethernet networks use various cable types.
• Common types are CAT 5e and CAT 6.
• "Twisted pair" cables (four pairs of copper wires twisted together) minimize signal interference.
• Other cable options include coaxial cable (single copper wire with insulation and shielding) and fiber optic cable (transmitting data as light signals). Fiber optic is expensive but superior, handling longer distances with high performance/bandwidth.