ITF+ Networking Notes

1. Basic Networking Concepts

• What is a Network?:
  • A network is a group of connected devices that share data and resources.

2. Network Types

• LAN (Local Area Network):
  • Small networks in a single location.
  • Example: Home network, small office.
• WAN (Wide Area Network):
  • Connects multiple LANs over large areas.
  • Example: The Internet.
• MAN (Metropolitan Area Network):
  • Covers a city or campus.
  • Example: City-wide public Wi-Fi.
• CAN (Campus Area Network):
  • Connects networks within a campus.
  • Example: University network.
• PAN (Personal Area Network):
  • Very small network for personal devices.
  • Example: Bluetooth connections.
• VLAN (Virtual LAN):
  • Groups devices logically, regardless of physical location.
  • Example: Isolating departments on the same physical network.

3. Wired Networking

• Definition:
  • Physical connections using cables for data transfer.
• Ethernet Cable:
  • Common categories: Cat5, Cat5e, Cat6, Cat6a.

4. Wireless Networking

• Definition:
  • Connections using radio waves or infrared.
• Wireless Access Point (WAP):
  • Allows wireless devices to connect to a wired network.
• 802.11 Standards:
  • 802.11a: 5 GHz, up to 54 Mbps.
  • 802.11b: 2.4 GHz, up to 11 Mbps.
  • 802.11g: 2.4 GHz, up to 54 Mbps.
  • 802.11n: Dual-band, up to 600 Mbps.
  • 802.11ac: 5 GHz, gigabit speeds.
  • 802.11ax (Wi-Fi 6): Improved speed and efficiency.

5. Networking Devices

• Switches:
  • Connect devices within a network and manage traffic.
• Routers:
  • Connect multiple networks and route data between them.
• Firewalls:
  • Protect networks from unauthorized access.
  • Types: Hardware firewalls, software firewalls, cloud firewalls.

6. Networking Types

• Fiber:
  • High-speed internet using light signals (e.g., Google Fiber).
• Cable:
  • Broadband internet over coaxial cables (e.g., Comcast Xfinity).
• DSL (Digital Subscriber Line):
  • Internet over telephone lines (e.g., AT&T DSL).
• Dial-Up:
  • Old technology using telephone lines (e.g., AOL Dial-Up).
• Satellite:
  • Internet via satellite connections (e.g., Starlink).

7. Networking Configurations

• IP Address:
  • Unique identifier for devices on a network.
• Subnet Mask:
  • Divides the IP address into network and host portions.
• Default Gateway:
  • Routes traffic from a local network to other networks.
• DNS (Domain Name System):
  • Translates domain names into IP addresses.

8. IP Addressing Methods

• DHCP (Dynamic Host Configuration Protocol):
  • Automatically assigns IP addresses.
• Static IP:
  • Manually assigned IP addresses for specific devices.

9. Wired Network Categories

• Ethernet Standards:
  • Cat5: Up to 100 Mbps.
  • Cat5e: Up to 1 Gbps.
  • Cat6: Up to 10 Gbps (short distances).

10. Networking Security

• Basic Concepts:
  • Protecting data and devices from unauthorized access.
• Wired Security Configurations:
  • Port Security: Limits access based on MAC addresses.
  • ACLs (Access Control Lists): Restrict or permit traffic based on IPs and protocols.
  • Physical Security: Locks, restricted access to equipment.
• Wireless Security Configurations:
  • Encryption Standards: WPA, WPA2, WPA3 (most secure).
  • MAC Filtering: Restricts access to approved devices.
  • SSID Configuration: Change default SSID and disable broadcast when needed.
  • Authentication: Use secure protocols like 802.1X for enterprise networks.

11. Questions for Review

1. What is the difference between LAN and WAN?
2. How does a VLAN improve network management?
3. What is the purpose of a wireless access point?
4. Compare DHCP vs. Static IP.