Module 1.1: Network Components 🌐

What is a Network?

• Definition: A system of interconnected hardware devices used to connect systems for sharing resources and exchanging information.
• Classic Example: The Internet, which is a network of networks interconnected for data exchange.

Benefits of Communication Networks

• Resource Sharing: Easy sharing of files, music, streaming from server to client.
• Reduced Cost: Interconnected systems lower individual costs.
• Ease of Software Installation & Distribution: Download and install directly from the internet.
• Improved Security: Centralized and flexible security measures.
• Workplace Flexibility: Access files from a cloud provider to work from anywhere.
• Reduced Cost of Peripherals: Less need for powerful devices, can use network resources instead.
• Centralized Administration: Perform administrative tasks once and propagate to all devices.

Categories of Network Components

1. End Device (Host) or Node:

   • Any device connected to a network to access information (e.g., servers, workstations, laptops, tablets, phones, printers, scanners, IoT devices).
   • Contains a Network Interface Card (NIC) for network connectivity (can be wired or wireless).

2. Interconnecting Devices:

   • Modem: Converts analog signals to digital for internet access (e.g., dial-up, DSL, cable, satellite).
   • Repeater: Extends the range of the network by passing along traffic.
   • Hub: Connects multiple hosts; repeats incoming signals to all ports (considered a "dumb" device).
   • Bridge: Connects two separate networks, allowing communication between them.
   • Switch: Connects end-user devices; smarter than hubs, only sends data to intended recipient (e.g., workgroup switch).
   • Router: Connects multiple networks (wired or wireless); makes path selection decisions for data packets.
   • Firewall: Monitors and controls incoming and outgoing network traffic based on security rules.
     • Host-Based Firewall: Software on an individual computer (e.g., Windows Firewall).
     • Network Firewall: Filters traffic for an entire network (e.g., LAN to Internet).

3. Network Media:

   • Wired: Ethernet cables for stable and stationary devices (e.g., desktop PCs).
   • Wireless: Wireless networks for mobile and flexible devices (e.g., laptops, IoT devices).
   • Modern networks often use a combination of both wired and wireless connections.