Networks are Everywhere Chapter Notes | Year 3 Computing IGCSE (Cambridge) - Class 3 PDF Download

Networks around us

• Computer networks are prevalent in various environments, including homes, schools, hospitals, and other places.
• The type of hardware devices in a network depends on the specific needs of the users in that environment.
• Typical network devices in schools:
  • Desktop computers: Stationary computers used for tasks like studying and administrative work.
  • Laptops: Portable computers used by students and teachers for flexible access.
  • Printers: Devices for printing documents, assignments, and other materials.
  • Scanners: Devices for digitizing physical documents or images.
  • Multifunction machines: Combine photocopying, scanning, and printing capabilities in one device.
  • Video projectors: Used to display content from a computer onto a screen or wall for presentations.
• Additional devices in some schools:
  • Tablets: Portable devices for interactive learning and note-taking.
  • Cameras: Used for photography or video recording in educational activities.
  • Interactive smartboards: Whiteboards connected to a computer and projector, enabling interactive teaching.
• Common devices in home networks:
  • Desktops: Stationary computers for general use.
  • Laptops: Portable computers for work, entertainment, or study.
  • Tablets: Used for browsing, reading, or casual gaming.
  • Smartphones: Mobile devices for communication, browsing, and apps.
  • E-readers: Devices designed for reading electronic books.
  • Gaming consoles: Devices for playing video games, often connected to online services.
  • Security cameras: Used for home monitoring and surveillance.
• Additional devices in some homes:
  • Smart devices: Include refrigerators, light bulbs, air conditioners, and heaters that connect to the home network for remote control and automation.
• Did you know?
  • Smart devices can be controlled remotely from anywhere in the world using the internet and a smartphone or tablet.
• Keywords:
  • Multifunction: Refers to devices that perform multiple tasks, such as a multifunction printer that can print, scan, and copy.
  • Interactive smartboard: A whiteboard connected to a computer and projector, allowing interactive content display and manipulation.
  • E-reader: A device specifically designed for reading electronic books.
  • Smart device: An electronic device that connects to other devices via the internet for enhanced functionality and control.

Services available on a network

• Networks enable computers and devices to collaborate, providing various services based on user needs.
• Main services available on most networks:
  • Sharing digital files: Allows users to access and share files across devices.
  • Communication: Facilitates email, instant messaging, and other forms of interaction.
  • Sharing printers: Enables multiple devices to use a single printer.
  • Access to the World Wide Web: Provides connectivity to websites and online resources.
• Additional services may be available depending on the network’s purpose and user requirements.
• Home network services:
  • Sharing digital files: Users can share files and folders across devices like smartphones, tablets, desktops, and laptops, accessible from anywhere in the home.
  • Shared printing: Multiple devices can send print jobs to a single printer connected to the network.
  • Communication: Users can send and receive emails or chat with others on the network using instant messenger services.
  • Access to the World Wide Web: Connects to the internet, allowing access to websites and online content.
  • Gaming and entertainment: Supports online video streaming and multiplayer gaming.
• School network services:
  • Communication: Users can send emails and use instant messaging for collaboration.
  • Shared printing: Multiple users can print to multifunction printers located anywhere in the school, with schools typically having multiple printers.
  • Shared storage: Data is stored centrally on the network, not on individual devices, allowing easy access and management.
  • Sharing digital files: Users can access files and folders from any device connected to the network.
  • Shared software: Software is installed centrally and accessible to all users, reducing the need for individual installations.
  • Access to the World Wide Web: Provides internet access, though schools may restrict certain websites for safety and focus.
• School networks are larger than home networks, supporting more devices and users, and offering services tailored to educational needs.
• Keywords:
  • Services: Functions or tasks that can be performed on a network, such as file sharing or printing.
  • World Wide Web: An internet service that allows users to find and view web pages.

Advantages and disadvantages of networks

• Advantages of networks:
  • Sharing devices:
    • Hardware like printers, photocopiers, and scanners can be shared among multiple users.
    • Sharing devices reduces costs by eliminating the need for each user to have their own device.
  • Sharing software:
    • Running software on a network is simpler than installing it on each device.
    • Networked software is often more cost-effective, as licenses can be shared across multiple users.
  • Sharing files:
    • Digital files, such as letters, photographs, videos, and other documents, can be easily shared among network users.
    • Facilitates collaboration and access to shared resources.
  • Shared storage:
    • Data is stored in a central location, making it easy to find and access.
    • Centralized storage simplifies creating backup copies of data and files.
  • Flexible access:
    • School networks allow students to work from various locations, such as classrooms or libraries.
    • Students can start work in one location and continue in another, enhancing flexibility.
  • Communication:
    • Networks enable easy communication between students, teachers, and other users, even if they are in different locations.
    • Supports collaborative work and efficient information exchange.

Disadvantages

Expensive to set up

• Setting up a network can be costly due to the equipment required.
• Equipment costs include:
  • Cables for wired networks: Necessary for establishing physical connections between devices.
  • Devices for wireless networks: Such as routers, access points, and network adapters to enable wireless connectivity.

Running the network

• Maintaining a network requires ongoing effort to ensure it operates smoothly.
• A dedicated person or team is needed to:
  • Monitor the network for proper functionality.
  • Troubleshoot and fix issues, such as connectivity problems or hardware failures.
• Network maintenance demands significant time and technical expertise.

Network failure

• A network failure disrupts access to network services, preventing users from performing tasks.
• Example: If a network breaks down, users cannot access shared files, impacting productivity.
• Causes of network failure may include hardware malfunctions, software issues, or external factors like power outages.

Computer viruses

• Computer viruses are malicious programs that disrupt normal computer operation.
• Viruses can spread easily across a network from one device to another, affecting multiple systems.
• Entry points for viruses include infected files, email attachments, or unsecured network connections.

Network security is expensive

• Security measures are essential to protect networks from threats.
• Purposes of security measures:
  • Protect the network from viruses and malware.
  • Safeguard personal and confidential information from unauthorized access.
• Implementing security measures, such as firewalls, antivirus software, and encryption, can be very costly.

Keywords

• Backup: An exact copy of an original file or data, created to prevent data loss in case of failure or corruption.
• Computer virus: A program designed to cause damage to data, software, or hardware, often spreading across networked devices.

What can you do?

• Understand the hardware devices used in school and home networks, such as computers, printers, and smart devices.
• Discuss the various services available on networks, including file sharing, communication, and internet access.
• Explain the advantages of networks, such as resource sharing and flexible access, as well as the disadvantages, such as high setup costs and security risks.