Computer Networks Overview

Computer Networks

• Consist of two or more computers linked to share resources and exchange data
• Types of computer networks include:
  • Local Area Network (LAN): Links computers within a building using direct cables, radio, or infrared signals.
  • Metropolitan Area Network (MAN): Links computers within a group of buildings using fiber-optic cables.
  • Wide Area Network (WAN): Links computers separated by miles or thousands, utilizing long-distance transmission media.

Networking Importance

• Reduced hardware costs: Users can share equipment.
• Connected people: People can work together irrespective of location.
• Shared applications: Users share software and applications through a server.
• Building information resources: Users create a common pool of data that is accessible by all employees.

Network Fundamentals

• Cables, telephone lines, coaxial cables, microwaves, satellites, wireless, fiber optics connect computers.

Network Devices

• Routers: Examine and transmit data to its destination.
• Switches: High-speed electronic switches maintain connections between computers.
• Protocols: Standards that specify how network components communicate.

Local Area Networks (LANs)

• Connect computers and peripherals within a building.
• Users can access software, data, and peripherals.
• LANs require specific hardware and software.
• Workstations or nodes are computers connected to a LAN.
• Types of LANs: Peer-to-Peer and Client-Server.

Network Bandwidth

• Bandwidth refers to the data transfer capacity of a transmission medium.
• Measured in kilobits per second (kbps), megabits per second (Mbps), and gigabits per second (Gbps).
• Example bandwidths: PSTN Twisted Pair (56 kbps), ISDN (128 kbps), TV Cable (1-10 Mbps).

Network Topologies

• Bus: Computers are connected in a linear arrangement through a common cable. All computers hear data sent out. Least expensive and easy to set up.
• Star: Centralized hub or switch connects all devices. Easier to install, and if there is a break in a cable it does not disturb the other computers.
• Ring: Devices connected in a ring, data passes around until it reaches the destination. Best at passing data with fewer collisions. More expensive and complex to install.

Network Media

• Twisted Pair: Two insulated wires twisted around each other (e.g., telephones).
• Coaxial Cable: Insulated center wire surrounded by a layer of braided wire (e.g., cable TV).
• Fiber Optic Cable: Glass fiber that transmits data as light impulses. Can carry more data over longer distances than other wire.
• Infrared: Wireless system using infrared signals for communication.
• Radio: Wireless system using radio waves to send and receive data.

Peer-to-Peer Networks

• All computers are equal, no dedicated file servers.
• Users decide which files and peripherals to share.
• Suitable for small networks.
• Easy to set up (e.g., home networks).

Client-Server Networks

• Typical in corporate settings.
• Use various topologies or physical layouts.
• Requires file servers, network computers, and network operating systems.
• Clients send requests to servers for programs and data access.

This quiz covers the fundamental concepts of computer networks, including types such as LAN, MAN, and WAN. Explore the importance of networking, the benefits of shared resources, and the devices that connect computers. Test your knowledge of core networking principles and devices.