Topic 1.4: Wired & Wireless Networks

Topic 1.4: Wired & Wireless Networks

1. The Internet

   • DNS: Domain Name System
   • Hosting: Websites stored on dedicated servers
     • Need to be available 24/7
     • Accessed by thousands of users at a time
     • Strong protection from hackers
     • They need an IP that doesn't change
   • The Cloud: Remote servers that store data that can be accessed over the internet
     • Access anytime
     • Anywhere from any device
     • Automatic backup
     • Collaborate on files easily

2. Network Performance

   • Bandwidth: The more data that can be transferred at a time
   • Number Of Users: Having a lot of people using a network means a lot of data is being transmitted
   • Transmission Media: Wired connections are faster than wireless. Fibre optic cables are faster than copper
   • Wireless Factors: Wireless can be affected by walls, distance, signal quality and interference from other devices
   • Topology: The layout of a network

3. Network Hardware

   • Network Interface Controller: Build in hardware that allows a device to connect to the internet
   • Switches: Connects a device on a LAN
   • Router: Transmits the data between networks
   • Wireless Access Point: A switch that allows devices to connect wirelessly
   • Transmission Media: The cables in a network can be twisted pair cables, coaxial cables or fibre optic cables

4. Virtual Network

   • A software based network
   • Increased security: more secure access to the network remotely
   • The network can easily be expanded with less impact on the infrastructure and cost
   • Log into work from home

5. Types Of Network

   • WAN: Wide Area Network
     • Large geographical area
     • Infrastructure is hired from telecommunication companies who own and manage it
     • Connected with telephone lines, fibre optics, or satellite links
   • LAN: Local Area Network
     • Small geographical area
     • All the hardware is owned by the organisation using it
     • Wired with UTP cables, fibre optics, or wireless using routers and wifi access points
   • Where all devices are connected
   • Advantages
     • Sharing resources and printers saves money
     • Access files from any computer in the network
     • Data is easily backed up and stored centrally on the server
   • Disadvantages
     • Purchasing hardware is expensive
     • Managing a large network is complicated
     • Viruses may be able to infiltrate the network and infect every computer

6. Client Server & Peer To Peer

   • Peer To Peer
     • All computers are equal
     • Computers serve their own files to each other
     • Each computer is responsible for its own security and back up
     • Computers usually have their own printer
     • No central server
     • Storage is distributed across all computers, and back ups must be done separetly
   • Client Server
     • A client makes requests to the server for data and connections
     • A server controls access and security to one shared file store
     • A server manages access to the internet, shared printers and email services.
     • A server runs a back up of data
     • Security controlled by central server
     • All users are reliant on the central server
     • Can support hundreds or thousands of computers
     • Back up is done centrally