Zusammenfassung der Ressource
NETWORKS
- 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
- 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
- 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
- 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
- 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
- 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