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How does broadband work?

Confused by all things broadband related? Read on to get in the know.

Broadband is a technology that transmits data at high speed along cables, digital networks or subscriber lines, and mobile phone networks.

The term 'broadband' refers to a wide range of frequencies which can be divided into channels. The most common type of broadband is ADSL, which is carried along BT phone lines, although cable (using new fibre-optic cables) and 4G mobile broadband are hot contenders to topple ADSL's dominance as both becoming increasingly available throughout the UK.

Back in the early days of the internet when there were less users, dial-up connections — where both the telephone and internet shared the same channel on phone lines — were fine. As more people started using the internet and usage became increasingly common, however, dial-up connections were no longer enough. Broadband developed from a need for greater amounts of information to be transmitted across the internet.

If you imagine a narrow motorway tunnel with hundreds of cars attempting to pass through at rush hour, that's what using the internet with a 56kbps dial-up connection was like. In this analogy, the best solution would be to add extra lanes, and it is on this principle that broadband is based.

If you want to find out more, take a look at the uSwitch What is Broadband? guide, which explains this in more detail.

how does broadband work?

How does ADSL broadband work?

ADSL broadband comes from your local telephone exchange, owned by BT, through a Fixed Line Access Network made out of copper wires. These are the telephone lines that you see in the street.

The lines in the street connect to the wiring inside your house and provide you with an internet and phone connection through the BT socket on the wall. At this point, there's also a piece of equipment called a microfilter, which separates out your telephone line from your broadband, allowing you to use the phone and internet at the same time.

The information that you initially receive in your home is a series of digital signals which are decoded and recoded into usable information, in this case for telephone calls and an internet connection. An ADSL broadband connection is 'always-on'.

How does cable / fibre-optic broadband work?

Unlike the copper wires of an ADSL connection, cables are partially made of fibre-optic material, which allows for much faster broadband speeds and increased reliability.

The other advantage of cable is that it also allows for the transmission of audio and visual signals, which means you can get both landline and digital TV services from your cable broadband provider.

How does mobile broadband work?

Mobile broadband uses 3G and 4G mobile phone technology. These are made possible by two complementary technologies, HSDPA and HSUPA (high speed download and upload packet access, respectively).

The connection is provided from mobile phone masts and is therefore available on the move or abroad. Although 4G coverage is increasing, it still isn't available everywhere just yet, so your speeds may slow down, depending upon where you are.

How does wireless broadband work?

Basically, the internet comes into your router and is then converted into a radio signal and broadcast. The wireless network card in your computer picks it up and re-encodes it again.

With the exception of mobile broadband, it is not the broadband connection that is wireless; it is the router and network card in your computer.

Like radio, the signals can be changed and set to different frequencies, so if one channel is too busy you can switch to another.

Now that you know how the different types of broadband work, visit our broadband postcode checker to see what types are available in your specific area.