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The UK is lagging behind other countries in the
push for next-generation broadband networks. Telecoms
firm BT has said it is unwilling to fund the roll-out of
a £15bn fibre optic network to every home in the UK, and
there are concerns over how such a network would make
money.
Find out more about the technologies that could one day
deliver faster broaderband to your home.
FIBRE TO THE HOME
Fibre to the home would bring speeds of between 50Mbps
and 100Mbps, with the added benefit of being able to
offer those speeds both upstream and downstream. This
would make contributing back to the net - sending video
files for instance - much easier.
Unlike DSL technologies - which are carried along copper
cables - it is not subject to noise issues.
Fibre optics are encased in cable similar to an ordinary
PC cable but inside are tiny, hair-size fibres of many
colours. They are used to transmit digital information
in the form of light signals
Providers such as BT would lay ethernet over the fibre
in order to provide services.
The biggest problem issue about fibre is the cost. To
provide fibre to the home across the UK would cost up to
£15bn.
BT is the most likely candidate to provide such a
network and while it has committed itself to putting
fibre in all new-builds, nothing else has yet been
decided.
VDSL (Very High Speed Digital Subscriber Line)
This is the cheaper option than fibre optics - UK
estimates are about £5bn for a nationwide rollout - and
it is basically a hybrid solution utilising both copper
and fibre.
VDSL will require the building of 90,000 new street
cabinets - where wires from the telephone exchange are
kept at street level - and is also known as Fibre to the
Cabinet (FTTC).
It is capable of supporting new high bandwidth
applications such as HDTV, as well as telephone services
such as voice-over IP and general internet access, over
a single connection.
VDSL is deployed over existing copper wiring and,
according to BT, can operate at speeds of up to 30Mbps
with the chance of getting faster as new flavours of it
are deployed.
Like ADSL it is still distance-dependent and those
closest to the exchange will get the fastest speeds.
VDSL cannot be incorporated into the existing telephone
exchanges because of interference issues.
Second-generation VDSL2 systems could provide data rates
exceeding 100 Mbps simultaneously in both the upstream
and downstream directions, with the maximum available
bit rate achieved at a range of about 300 meters.
ADSL2+
This variant of existing DSL is being rolled out in the
UK from April 2008 with every exchange enabled by 2011.
The arrival of ADSL2+ is closely linked to work BT has
been doing on its core network, upgrading it to an IP
infrastructure in a project known as the 21 century
network. ADSL2+ offers speeds of up to 24Mbps, but as it
is distance-dependent a lot of people will not actually
achieve those kind of speeds.
Because the copper lines it operates on pick up
electro-magnetic noise the line can be affected by some
unusual issues, such as noisy fridges.
Old houses with old internal wiring will also affect the
service, with possible breaks in service or speed
slowdowns.
WIMAX
Wimax stands for Worldwide Interoperablity for Microwave
Access. It is based on the IEE 802.16 standard, also
known as WirelessMAN.
It is often referred to as wi-fi on steroids, because of
its ability to provide wireless data over much longer
distances than wi-fi.
In countries with good fixed line infrastructure, WIMAX
acts as a filler but in some developing countries is can
be the dominant infrastructure for broadband access.
Countries such as Pakistan are planning nationwide WIMAX
rollouts.
It is possible for WiMAX can deliver speeds of up to
70Mbps and operate over distances up to 50km, although
not the two together.
CABLE
Cable Broadband has three major parts - the customer
cable modem (which connects to the customers PC or
laptop), the cable TV network (through which the signal
flows) and the main cable router (which take the
customer signal off the cable TV network and passes it
on to the Internet).
The system which is used, or "the protocol", is called
DOCSIS (Data Over Cable Service Interface
Specification).
Currently DOCSIS 1.0 offers speeds up to 38Mbps. The new
system, called DOCSIS 3.0, could offer up to 120Mbps and
higher. This (D3) is currently in trial at 50Mbps in
selected regions of the UK, such as Ashford, Folkestone
and Dover.
The system is always on, it is not dependent on the
distance you are from the exchange (unlike ADSL) and
every person can receive the same speeds - unlike ADSL.
The electronics are a mixture of fibre and copper cable,
with the majority being fibre. Only the last part to the
customer is copper which means that cable broadband has
the potential to offer far greater speeds now, and in
the future, compared to its DSL rival.
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