OCR GCSE 1.3.1

OCR GCSE 1.3.1

1. Types of Networks

   • LAN
     • Local area network
       • Located in a single small geographic area
   • WAN
     • Wide area network
       • Connects multiple local area networks
       • Infrastructure is leased from telecommunication companies
   • Network
     • A network is two or more computers connected to each other for the purpose of communication
       • Advantages
         • file sharing - users can share files with other users
         • roaming access - users can sign in to any computer on the network and be able to access their files.
         • centralised maintenance and updates
         • levels of access
       • Disadvantages
         • cost - additional equipment is needed to allow computers to communicate
         • spread of malware
         • management - networks require management by technical staff such as a network manager

2. Hardware

   • modem
     • Changes electronic signals to analogue signals and vice versa to be transported across telephone cables
   • Wireless access point
     • allow devices to connect to a network without cables
   • Routers
     • They are used to send data signals across the internet. Routers work by collecting knowledge of available routes to transmit data. They then determine the most suitable route for sending data.
   • Switches
     • Switches are network devices that record which computers are connected to which ports. When traffic is received, the switch forwards the traffic to its intended recipient only.
   • NIC
     • Integrated cards that contain a protocol to determine how the connection should work.
   • Transmission media
     • copper Cables
     • Fibre -optic cables

3. Network performance

   • Number of users
   • Bandwidth
   • Transmission error

4. Network topology

   • Star Topology
   • Mesh Topology

5. Internet

   • The internet is a large collection of WANS
   • Connecting, to the internet