networks

networks

1. topologies

   • bus
     • where all devices are connected by one cable
     • is the cable snaps all devices will break
   • star
     • a star network is where all devices are conected to the sever from different cables
     • if one computor breaks then only that computor will be unconnected, all others will be fine
   • ring
     • a ring network is where computors are connected to each other in a ring
     • so if one wire snaps only 2 devices will be unconected

2. WAN

   • wide area network
   • A network that spans a large area or multiple organisations

3. LAN

   • local area network
   • A network in a small area or single organisation

4. network

   • a network is a connection of shared devices
   • advantages
     • Consistent User Experience - You can log on to any computer in the school using the same username and password Your files are available on every computer you use, even if you created them on a different computer You can print, use the Internet, email and use the same software on any computer
   • disadvantages
     • What disadvantages could there be to putting computers on a network? Expensive – extra hardware and wiring needed More room for error – if something goes wrong it can affect every computer Difficult – it requires a technical expertise Malware – viruses and other malicious software can spread through the network

5. IPaddreses

   • An IP address is an internet protocol address, it must be unique because the data could be sent to the wrong person it is assigned to every computer on a network, used to identify it. messages on a network have an IP address attached, which is how a computer knows whether or not to keep the message.
   • Globally, there are now more devices on the Internet than the 4’228’250’625 devices it’s possible to assign a unique address to
   • We get round this by assigning an “external” IP address to each house or business, then “internal” IP addresses to the computers in that house or business
   • Only the external IP addresses need to be unique, the internal computers are not directly accessible