NETWORKS

NETWORKS

1. advantages

   • share resources
     • such as printers and internet connections
   • share logins
     • the same username and password can be used on every computer on the network
   • share files
     • the same files are available whichever computers you use

2. disadvantages

   • cost
     • networks are expensive to set up
     • extra hardware and wiring needed
   • increased risk
     • problems such as viruses can affect every computer on the network
   • difficulty
     • expertise is needed to set up and maintain a network

3. types of network

   • LAN
     • Local Area Network
     • a network contained in a single geographical location or organisation
   • wan
     • Wide Area Network
     • a network that spans a large geographical area, or multiple organisations
     • often consists of multiple LANs networked together

4. Topologies

   • bus topology
     • Advantage: cheap to install
     • Disadvantages: high chance of catastrophic failure, lots of collisions, slows down as more computers are added
   • ring topology
     • advantages: cheap to install, no collisions(fast)
     • disadvantages: high chance of catastrophic failure, difficult to expand
   • star topology
     • advantages: low chance of failure, no collisions(fast)
     • disadvantages: expensive, depends on a switch

5. IP Address

   • computers on a network need an address to identify them.
   • when a computer is added to a network it is assigned an IP Address(internet Protocal Addresss)
   • the IP Address is an unique value assigned to each computer
   • Each IP Address on a network must be unique

6. mesh

   • the interenet
     • it is impossible to break the internet, since another route can always be found.
   • there are multiple different routes between any two nodes
   • a cost is assigned to each connection in a mesh
   • route-finding algorithms are used to find the lowest cost route between two nodes.
   • data is split into small chunks called packets
   • each packet is sent along the lowest cost route
   • the packets are re-assembled on the other side

Imagens e arquivos do mapa