Design Your Own Network: Shape and Size | Year 9 Computing (Cambridge) PDF Download

Basics of Network Design

What is Network Design?

Network design is the planning of a computer network's infrastructure. It involves determining the layout, hardware, and configuration needed to establish a functional network.

Key Components

• Nodes: Devices such as computers, printers, and servers.
• Links: Connections between nodes, which can be wired (Ethernet cables) or wireless (Wi-Fi).
• Protocols: Rules that govern data transmission, like TCP/IP.

Network Topologies

• Bus Topology: All devices are connected to a single central cable. It's simple and inexpensive but can be slow if many devices are connected.
• Star Topology: Devices are connected to a central hub. It's easy to manage and troubleshoot but can be expensive due to the hub.
• Ring Topology: Devices are connected in a circular fashion. Data travels in one direction, which can reduce collisions, but a break in the ring can disrupt the network.
• Mesh Topology: Devices are interconnected. This offers high reliability and redundancy but is complex and costly.

Types of Networks and Their Configurations

• Local Area Network (LAN):
  • Covers a small area like a home, school, or office.
  • Offers high-speed connectivity.
  • Example: A school network connecting computers in different classrooms.
• Wide Area Network (WAN):
  • Covers a large geographic area, like cities or countries.
  • Connects multiple LANs.
  • Example: The internet or a company's network with offices in different cities.
• Metropolitan Area Network (MAN):
  • Spans a city or a large campus.
  • Larger than a LAN but smaller than a WAN.
  • Example: A city's public Wi-Fi network.
• Personal Area Network (PAN):
  • Very small network, often within a single room.
  • Connects personal devices like smartphones, laptops, and tablets.
  • Example: Bluetooth connection between a phone and a laptop.
• Network Configurations:
  • Client-Server Network: Centralized control with dedicated servers providing resources to client computers.
  • Peer-to-Peer Network: Decentralized, with each device acting as both a client and a server.

Planning and Designing a Network

Steps in Network Design

• Assess Needs:
  • Determine the number of users.
  • Identify the types of devices to be connected.
  • Understand the data traffic and bandwidth requirements.
• Choose Network Topology:
  • Select a topology based on the size, scale, and purpose of the network.
• Select Hardware:
  • Choose appropriate routers, switches, and cabling.
  • Ensure devices support necessary speeds and protocols.
• Design Layout:
  • Plan the physical layout of devices and cables.
  • Consider future expansion needs.
• Implement Security Measures:
  • Set up firewalls, anti-virus software, and encryption.
  • Implement access control and user authentication.
• Test and Optimize:
  • Test the network for performance issues.
  • Optimize configurations for speed and reliability.

Example Scenario: Setting Up a School Network

• Needs Assessment:
  • 100 computers across 10 classrooms.
  • High-speed internet for online learning.
  • Secure access for students and staff.
• Topology Selection:
  • Star topology for easy management and troubleshooting.
• Hardware Selection:
  • High-speed switches for each classroom.
  • A robust router with firewall capabilities.
• Layout Design:
  • Central server room for main connections.
  • Ethernet cables running to each classroom.
• Security Measures:
  • Firewall to protect against external threats.
  • User authentication for accessing network resources.
• Testing and Optimization:
  • Conduct speed tests in each classroom.
  • Adjust settings to minimize latency and maximize speed.