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Broadband Glossary - Broadband Terminology Explained

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With broadband terminology often providing confusion, we've produced a comprehensive list of broadband terms and their meanings which we hope you will find helpful and useful.

Acceptable Use Policy or Fair Use Policy

Most broadband suppliers who offer unlimited broadband downloads have an acceptable or fair use policy. The supplier monitors the broadband usage by the customer. If the use is deemed excessive, the provider retains the right to restrict or stop the customer using the service. The restrictions are usually triggered by excessive downloading. The restrictions allow other customers to access the broadband service fairly.


This stands for Asymmetric Digital Subscriber Line. This is now an older technology that was developed for enabling broadband connections using existing telephone networks.

ADSL Filter

ADSL filters allow you to continue to make telephone calls whilst using your broadband connection. The filters are easy to install: unplug your telephone from the wall socket, connect an ADSL filter into the wall socket and reconnect the telephone to the ADSL filter socket marked 'PHONE'.

Alternative Networks (Alt Nets)

Alt Nets are smaller broadband infrastucture suppliers. Their fibre networks have less geographic coverage compared to the main Internet Infrastructure Providers. Examples of Alt Nets include Hyperoptic, Community Fibre, KCOM, Giganet, Gigaclear, Jurassic Fibre and Toob.

Always On

A connection to the Internet that is permanently available and ready for use.

Antispam Software

A program running either on the internet or on your computer that analyses incoming mail and filters spam (junk) mail.

Antivirus Software

A program running on your computer to protect it against a virus attack. Viruses are malicious code sent from other computers which can intrude on your privacy, damage your computer or corrupt your files.

Asymmetrical Speeds

This is when the broadband download and upload speed of a broadband package is different, with the upload speed less.


The maximum amount of data that can be transferred over an Internet connection at any one time. Bandwidth is measured in Mbps or Gbps.


A connection to the Internet that works at high speeds because of its greater bandwidth.


The generic name given to services which use fibre optic cable buried underground to carry telephone, television and broadband to your home.

Cap (Broadband Download Limit)

The amount of data per month an Internet Servie Provider (ISP) allows you to transfer to your computer via broadband before either stopping, or charging you. Nowadays, most ISP packages do not have a cap or broadband download limit, but may operate an Acceptable / Fair Usage Policy as described above.


CityFibre is the UK's third largest Internet Infrastructure Provider. It is currently building its own full fibre broadband network across the UK. Around 3 million homes can currently access their gigabit network, with plans for 8 million homes by 2026. ISP's like Vodafone, Zen and TalkTalk are using CityFibre's full fibre network to supply broadband services to their customers.

Contention Ratio

This describes the maximum number of users sharing the bandwidth on the broadband connection between your local exchange and your broadband provider.

Contract Period

A contract period is the minimum length of time you will be tied with your existing broadband provider. The standard period is 24 months, though some broadband suppliers offer 12 month contracts and rolling monthly contracts.


The old dial-up connection used a telephone line to connect to the Internet. A modem turned data into audio signals so that it could literally 'dial' the number of an internet service provider (ISP) and communicate with their computers.

Digital Voice

Digital Voice is the new technology replacement for the UK's old and antiquated analogue landline network. Using Digital Voice, landline phone calls will be made over the Internet using digital phones that are connected to a broadband router as opposed to the old telephone sockets. This industry-wide shift from analogue to digital landlines using VoIP is scheduled to be completed by the end of 2025.


Describes the process of transferring files from a location on the internet to your PC, laptop, smartphone or other smart device.

Download Speed

The rate at which files are transfered from a location on the internet to your PC, laptop, smartphone or other smart device. Download speeds are measured in Megbits per second (Mbps) or Gigabits per second (Gbps). The broadband speeds advertised by Internet Service Providers are average download speeds that are available to at least 50% of their customers at peak times (8pm-10pm).

Fair Use Policy

See Acceptable Use Policy.

Fibre Optic Broadband

A type of broadband that runs underground as opposed to the old ADSL broadband that runs from the telephone exchange to the steet-level cabinet and on to your home over ageing and degrading copper telephone wires. Fibre optic broadband is much faster than the old ADSL broadband and can offer broadband speeds up to 1,000Mbps (1Gbps) and higher in some areas.


Software or hardware that is designed to prevent unauthorised access to a network. This can either be a piece of software or a standalone piece of equipment.

Fibre To The Cabinet (FTTC) Broadband

This is a type of fibre broadband that uses fibre optic or coaxial cable from the exchange to the street-level cabinet, and then uses the existing copper wire cable to the home. With top average download speeds of 67Mbps, superfast FTTC Broadband is available to 97% of UK homes.

Fibre To The Premise (FTTP) Broadband

This is a type of fibre broadband that uses fibre optic cable all the way from the telephone exchange to the premise (either a home or business). No old copper wire cable is used. With gigabit capable download speeds in excess of 1,000Mbps (1Gbps), FTTP Broadband is being rolled out across the UK by a number of infrastructure providers. Around 52% of UK homes can access FTTP broadband.

Full Fibre Broadband

This is another name for Fibre To The Premise Broadband (FTTP). A full fibre broadband connection only uses fibre from the telephone exchange to the home or business, thus providing greater broadband speeds and reliability.

Gigabit Broadband

Gigabit Broadband is broadband capable of download speeds in excess of 1Gbps (1,000Mbps). Around 75% of UK homes can now connect to gigabit-capable broadband networks built by the likes of Openreach, Virgin Media and CityFbire.

GB (Gigabyte)

One gigabyte is approximately 1,000 megabytes. The Broadband caps or limits of a broadband package used to vary from 10GB to unlimited, depending on which broadband deal you chose. Nowadays, unlimited broadband downloads are standard in the industry.

Gbps (Gigabits per second)

The rate (broadband speed) at which broadband data is transferred between computers. One gigabit is approximately 1,000 megabits.

Internet Infrastructure Provider

An Internet Infrastructure Provider builds, maintains and supports a backbone broadband network. In the UK, there are 3 main Internet Infrastructure Providers, Openreach, Virgin Media and CityFibre. These networks are used by ISP's like BT, Sky & TalkTalk to provide broadband services to UK households.

ISP (Internet Service Provider)

An ISP is the company that provides your broadband connection.


A landline is set of physical copper lines that carry phone signals which connect homes and businesses to the UK phone system. The UK's existing analogue copper landline network is ageing & degrading and will be closed down by 2025. It is being replaced with Digital Voice, which is essentially making and receiving calls over your home's Internet connection instead.

MAC (Migration Authorisation Code)

This code used to allow you to migrate from one broadband supplier to another. Customers wanting to switch broadband supplier had to obtain their MAC code from their existing supplier. Nowadays, in most instances, the broadband provider you are switcing to contacts your existing provider and handles the whole switching process for you.

Mbps (Megabits per second)

The rate (broadband speed) at which broadband data is transferred between computers. One megabit is approximately 1,000 kilobits.

Mesh Network

A mesh network is typically a group of Wi-Fi routers or nodes that are tuned together to create one single network in your home. Home mesh networks have become popular as they often provide better broadband speed and coverage around the home compared to Wi-Fi extenders.

Mobile Broadband

Mobile Broadband is internet access provided to a device from a 3G, 4G or 5G mobile phone network like EE, Vodafone, Three and Virgin Media O2.


This is an acronym derived from the words modulator and demodulator by taking the "mo" and "dem" from the words. A modem is a piece of hardware that is used to connect to the Internet.

Modem Only Mode

This is a term used to describe when you put a Wi-Fi router into 'modem only mode'. This essentially turns off all the other router functions and converts the router into a stand-alone modem. People often do this to connect their own Wi-Fi kit to the modem and thus improve the Wi-Fi connectivity and speed around their house.


This is an audio file format which uses compression software to make the file size smaller without significant reduction in quality. It used to a common file format for sharing music files on the internet, before streaming became popular.


Ofcom is the UK's regulator and competition authority for the phone, telecoms and Internet industry. It is responsible for overseeing and protecting the interests of the UK public in these industry sectors and other Communication sectors such as TV and radio.


Openreach, part of the BT Group, is an Internet Infrastructure Provider responsible for running, maintaining and supporting some of the UK's largest broadband networks - including all the lines, cables, ducts, telephone exchanges and cabinets. Openreach is currently rolling out its gigabit-capable Fibre To The Premise (FTTP) network across the UK. Over 11 million UK premises are now covered with plans to connect a total of 25 million UK homes by 2026. ISP's like BT, Sky and TalkTalk use the Openreach networks to provide broadband services to their customers.


This is the act of tricking someone into giving them confidential information or tricking them into doing something that they normally wouldn't do or shouldn't do.


A device which is connected to the Internet and sends information to laptops, smartphones, computers, gaming consoldes and other smart devices over Wi-Fi.

Satellite Broadband

Satellite Broadband, as the name suggests, is internet access provided from satellites. It is often used in rural areas where traditional fixed line broadband or mobile broadband is either unavailable or very poor in speed, signal strength and reliability. Space X's Starlink is a satellite broadband provider and has been available in the UK since 2021.


Any software that covertly gathers user information through the user's Internet connection without his or her knowledge, usually for advertising purposes.

Static IP Address

A static IP address is an IP address given to a Internet connected device. They are useful when external websites or devices need to remember an IP address. An example in the home is a Wi-Fi printer.


An alternative to downloading large files such as music and video. Streaming allows users to instantly do things like play music & watch films over the Internet.

Symmetrical Speeds

This is when the broadband download and upload speed of a broadband package is the same.


Describes the process of transferring files from your PC to another location on the internet.

Upload Speed

The rate at which files are transfered from your PC, laptop, smartphone or other smart device to a location on the internet. Upload speeds are measured in Megbits per second (Mbps) and are not always the same as download speeds.

Voice Over IP (VoIP)

Voice over IP (VoIP) is a technology that enables phone calls to be made over the Internet. The UK's new digital landlines that are replacing the old copper landlines use VoIP.

Virgin Media

Virgin Media, part of Virgin Media O2, is an Internet Infrastructure Provider and ISP. Its Hybrid Fibre Coax (HFX) cable network with DOCSIS 3.1 technology covers around 16.1 million UK homes and can provide top average broadband download speeds of 1Gbps. Virgin Media is currently upgrading this network to XGS powered FTTP broadband which will improve network capacity, provide symmetrical download & upload speeds and reduce its latency/ping rates. It is anticipated that this upgraded network, alongside its Nexfibre FTTP rollout, will eventually cover 23 million UK homes by 2028 and provide wholesale access to other ISP's.

Web Space

The amount of storage space you get on a server to enable you to store emails or run a website.

Wi-Fi (Wireless Broadband)

Radio-based systems that allow transmission of information between a router and personal devices like smartphones and laptops without a physical broadband connection being required.

About The Author, Steve Tattersall

Steve Tattersall Steve Tattersall is a broadband technology writer with 20 years experience within the Internet industry. Based in Hampshire, England, he founded the BBC recognised broadband information site,, in 2004 and is currently the Director Of Marketing & Operations. During this time he has helped thousands of people across the UK with their Internet requirements by compiling a comprehensive range of broadband information, comparison tools and guides, all delivered on A graduate of Buckinghamshire New University (Brunel Business School) with a first class honours degree in Business, Steve has first hand experience of working for a broadband provider, having had a previous career at the broadband supplier NTL. Following its merger with rival Telewest, NTL is now known as Virgin Media, one of the UK's leading broadband, phone & TV providers. If you would like to contact Steve, please visit the contact us page or follow him on Twitter, LinkedIn and Quora. You can also find out more about on our about us page.

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