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.
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.
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 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 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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