7.2.4 & 7.2.7

• LAN (Local Area Network)


  A computer network that links devices within a building or group of adjacent buildings – with a radius of less than 1km
• WAN (Wide Area Network)


  A computer network in which computers connected may be far apart- with a radius of more than 1 km
• PAN (Personal Area Network)


  A computer network for interconnecting electronic devices centered on a individual persons workspace
• Network topology


  The arrangement of the different network elements (links, nodes etc.) of a communication network
• Logical network topology


  The higher level idea of how the network is set up, including which nodes connect to each other and in which was, as well as how data is transmitted through the network. Includes any virtual and cloud resources.
• Physical network topology


  The actual connection (wires, cables, etc.) of how the network is arranged. Setup, maintenance, and provisioning tasks require insight into the physical network.
• Star topology


  Every node connects to the central network device (like a hub, switch or computer). The central network device acts as a server and the peripheral devices act as clients. Allows for most transmissions to be distributed even if one of the computers goes down. Commonly used for wired networks.
• Star topology


  • Robust/client failure doesn't cause whole network failure
  • Collisions don't happen/ avoiding the need to re transmit packets
  • Causes if network failure are easy to identify/ reducing downtime
• Star topology


  • Higher cost/ using a switch or router as a central network drive
  • CND determines performance and no. Of nodes
  • If the central network device fails the whole network fails
• Mesh topology


  A network where each computer each connected with each other. Used to ensure transmissions are distributed even if one computer goes down. Commonly used for wireless networks.
• Tree topology


  A special structure where elements are like the branches of a tree. Uses elements from both star and bus topologies. Only ever one connection between two connected nodes. Used for wired networks.
• VLAN (Virtual Local Area Network)


  Allows a network administrator to set up separate networks by configuring a network device, such as a router, without cabling. Allows a network to be divided, set up, and changed, allowing a network administrator to organise and filter data accordingly.
• Components of a star topology

  • Router
  • Client