This is the measure of how
much data can be
transferred in a time
The higher the bandwidth
the more data that can be
transferred
Often measured in Mbps which is bits
per second or Mpbs which is bytes per
second
The more frequencies
available on a channel
the faster it is
Bottleneck
A bottleneck is the smallest bandwidth that
exists between the user and the place that
data is being downloaded from
The data even though it may have been travelling more
quickly before will get slowed down at the bottle neck
Cables
Copper Cable
Modern copper cables are in twisted pairs, this is
narrow wire that is insulated and twisted in twos,
without an earth wire- known as a UTP or Ethernet
cables, this can sometimes result in loss of data.
There are also STP cables, these do have
an earth which is a metal shield that
reduces electromagnetic interference,
these have a higher bandwidth capability
so are used in high speed networks
Coaxial cables which were used in older networks and is still
used in the television industry as it has a capacity for high
bandwidth. This has two wires and the outer cable acts as a
shield to electromagnetic interference.
Optical Cable
Fibre-optic cables use small
glass tubes to reflect light
along the tube
These have much higher bandwidth
as they do not have any electrical
interference
Wireless
These can be radio, satellite and infra-red.
This has a lower bandwidth than the wired methods
Can be interrupted by physical
obstacles such as walls
Importance of
bandwidth
The importance of bandwidth
depends on what it is being used
for
If something is being streamed then a large
bandwidth is needed
If something is being downloaded overnight then it
does not matter too much as it is going to be used
the next morning or day
Live/real time data needs a high
bandwidth as if it does not then it will
freeze and not work well