Confused by broadband? Want to know your Bandwidth from your Backbone, or your 3G from your Gigabyte? Try our broadband glossary and definitions.

How to use the broadband glossary 

A

ADSL
ADSL means asymmetric digital subscriber line. If you receive broadband via your phone line it will most probably be ADSL. It is asymmetric as the data download speed is faster than the upload speed. The maximum download speed for ADSL broadband is 8Mb. Most (but not all) areas  of the UK can now receive ADSL broadband.

Although ADSL broadband is delivered via phone lines, BT is not the only supplier. Other broadband providers can buy access to the “local loop” from BT Wholesale and re-sell ADSL broadband to the consumer. 

Algorithm
An algorithm is a process, formula or method for solving a problem (usually mathematical). On the web, you are most likely to come across algorithms in relation to search engines. For example, the Google search algorithm is a method of finding the most appropriate search results for a particular search query. 

Asynchronous
In broadband terms, this refers to different upload and download speeds. With ASDSL broadband (via a phone line) the download speed is faster than the upload speed - it is asynchronous.

Attenuation
The loss of the broadband signal as it makes its way from your exchange to your home, attenuation can be caused by the distance between you and the exchange, or poor quality cables. It is measured in decibels (Db).

B

Bandwidth
Bandwidth is the amount of data that can be transmitted over your broadband connection during a period of time. The more bandwith that is available, the more data that can be transferred during that time, and the faster your data (such as a webpage, or a film trailer) will download to your computer.

Broadband
A broadband connection can transfer more than one type of data at the same time, and at high speed, so you can have internet access and phone on one line.

Broadband download speeds start at 512kb and in the UK go up to a maximum of around 24Mb. Some countries already have home broadband services with download speeds of up to 100Mb. Broadband connections are often referred to as “always on” as you do not need to dial up to use the service. Broadband connections are two-way, so you can also upload content to the web. However most consumers will have broadband that is asymmetric, with a slower upload speed than download speed.

Broadband Checker
A broadband checker checks your BT phone number or postcode against a database of broadband packages available in the UK, and returns a list of broadband packages and bundles available in your area.

It is usually worth searching on phone number and then postcode for the most accurate broadband results. Search on your BT phone number to find packages delivered via your BT-installed phone line (your phone number is linked to your local exchange) and on your postcode for more accurate information on cable broadband availability.

You can try our free broadband checker, top left.

Broadband Provider
A broadband provider, or ISP, offers broadband services (home and/or business broadband packages) over an internet connection. 

Bundle
A bundle is comprised of more than one communications service, for example broadband and phone, or broadband and TV, or a triple play bundle such as broadband, TV and phone. Some of the best broadband offers may only available as part of a broadband bundle, eg a broadband/phone combination. This is because many broadband providers may make more money on phone calls than on fixed price broadband.

Many broadband providers offer bundled services - two key ones are BT and Tiscali.

C

Cable Broadband
Broadband delivered via cable - rather than a BT phone line - is available in mainly urban areas of the UK. There are two cable broadband providers in the UK - Virgin Media and Wight Cable (operating on the Isle of Wight). Virgin Media is currently offering cable broadband at up to 20Mb download speeds - it can do this as cables are robust and relatively new.

Contention Ratio
Contention is a feature of ADSL broadband services. The contention ratio refers to how many other subscribers share the network connection with the exchange. With a contention ratio of 20:1,  20 subscribers are sharing that bandwidth (although they may not be online at the same time). The more subscribers who are online, the slower the connection will be.

Home broadband packages typically have 50:1 contention ratios, thoug business broadband packages may have contention ratios of 20:1 or even 10:1. it is becoming less common for broadband providers and ISPs to advertise their contention ratios.

Convergence
In the telecoms and IT sectors it usually means two or more different technologies meeting in one device, such as a mobile phone with internet access. The delivery of broadband, voice and video over one line is often seen as the prime example of technological convergence.

From a consumer point of view, convergence can bring more complex technologies to users via another technology they are already familiar with and comfortable using, eg using TVs for browsing online, or for watching TV shows downloaded from the internet.

Some key companies taking advantage of this are Apple (with their iPhone),  Setanta Sports (with their Setanta by Broadband online sports TV service), BT with BT Vision (a catch-up and on demand service) and BBC iPlayer.

Cookies
Cookies are small files, often including an anonymous unique identifier, which are dropped on to your computer’s hard drive when you visit a website, and which provide information to the website on how you use that site.

Cookies are very common - if you don't want them you can delete them, or set up your browser to refuse cookies. However they often hold information that saves you time, such as registration details - so if you refuse or delete cookies you may have to repeatedly input information each time you visit a particular website.

D

Dead Zone
This is an area where wireless or mobile devices can't work, or where they have extremely limited connectivity, because of a lack of mobile or wireless broadband signal.

Digital Divide
There is a gulf between those sections of the population that have access to the internet and other digital technologies, and those sections of the population that do not. This is known as the digital divide.

As so many services (both commercial and governmental) become available online, groups without digital access (which can be caused by, for example, high cost, lack of skills, location, or a combination of these) are being left behind, and are therefore likely to miss out on opportunities that are available to people who have internet and other technological access.

Download Allowance
The download allowance is the amount of data that can be downloaded in one month. They are usually referred to as GB, Gigs, or Gigabytes. A small monthly download allowance may be only 2GB. Many broadband packages now offer unlimited download allowances - however these come with fair use policies which allow the broadband provider to limit the activities of very heavy downloaders who continue to download very large amounts of data at busy times (usually bwetween 6pm and 11pm). 

Some broadband packages with fixed download limits may let you buy more download allowance. Alternatively, if you regularly go over your monthly download limit you may be asked to upgrade to a broadband package with a larger download allowance.

E

Encryption
Encryption is a way of disguising data so it can be sent via the web safely, without unauthorised people reading it en route. The form encrypted data takes is called cypher text. Encryption is essential for online shopping as it means credit card information can be kept private.

Ethernet
Ethernet is a standard (IEEE 802.3 ) originally developed by the Xerox Corporation for use in local area networks (LANs). It can link several devices on one cable - all devices linked to the cable can communicate with any other device on the cable.

Ethernet originally  transmitted data at up to 10Mb. However Fast Ethernet, which transmits at up to 100Mb is now available. Gigabit Ethernet transmits at up to 1000Mb.

F

Fair Use Policy
A fair use policy is often included in broadband packages that offer unlimited download allowances. These policies can be used for traffic shaping - limiting downloading by very heavy downloaders at particularly busy times (usually 6pm to 11pm). As broadband subscribers with the same provider share bandwidth, if a few people are downloading extremely large amounts of data it can slow the service for other users online at the same time.

Fibre Optic
Fibre optic cable is used to carry signals for broadband, TV and voice. Made of very thin strands/threads of glass or plastic that can carry large amounts of digital information for long distances using light, fibre optic cables can carry a lot more data at one time than traditional copper wires.

Fibre optic cables are reliable (they don’t suffer from electromagnetic interference,) but they are expensive to install.

G

Gateway
A gateway is an entrance where two networks meet, eg a home network and the internet. A router sits at this gateway, determining the best route via which to send packets of information to their destinations. Gateways are often situated between an office or private (home) network and the internet.

Gigabyte
A gigabyte is made up of 1024 megabytes (a megabyte is eight times a megabit). Gigabytes are often referred to as GB or Gigs. Download allowances are usually referred to in terms of gigabytes - this refers to the amount of data that can be downloaded within one package (data could be a webpage, song, film trailer, or email, for example). A GB download allowance refers to an amount of data, not the speed at which data is transferred.

H

Hotspot
A hotspot is an area where wireless internet access is available to anyone with a wireless-enabled laptop. There may be a charge for accessing the wireless network, although BT Total Broadband packages come with a number of free wifi minutes each month for hotspot access. Although hotspots are often set up as such, a hotspot could simply be someone else’s unsecured wireless network.

I

Internet Accelerator
An internet accelerator speeds up usage of broadband, dial-up or mobile internet access by reducing the size of each webpage before it downloads to your pc. An internet accelerator does not actually increase the speed of your web connection - it simply compresses each element of a web page or email using Content Sensitive Compression (’CSC’) so that your data (eg a webpage, song or email) can be downloaded more quickly. Internet accelerators include Onspeed.

IP Address
An IP (Internet Protocol) address is a unique identifying address given to every computer connected to the internet. It is made up of four sets of numbers with each set separated by a dot. Each set of numbers is between 0 and 255. Computers accessing the internet may be allocated a temporary IP address by their ISP, although a website will require a fixed IP address. Some broadband providers will include a free IP address with their broadband packages.

J

K

L

Latency
Latency refers to the delay caused by the time it takes for data to travel between communicating devices, eg two computers playing an online game.

A fast, effective network needs low latency and high bandwidth. With a high latency network, data takes longer to be transmitted and this can adversely affect the performance of applications that require a fast response to operate effectively.

M

Mac-compatible broadband packages
Many UK broadband packages are Apple Mac-compatible. However not every broadband provider will offer the same level of support to someone using Mac-related broadband hardware as they do to pc users. We list several mac-compatible broadband providers and broadband packages.

Mp3
Mp3 stands for MPEG 1 Audio Layer 3. This is a technology that digitally compresses audio files, so reducing them to a fraction of their original size without affecting sound quality. This compression means they are small enough to download quickly via broadband.

Mobile Broadband
Mobile broadband allows you to access the internet while out and about - you are no longer limited by the length of cable from your fixed router, or your wireless network. A dongle, USB modem or datacard plugs into your laptop and accesses the relevant mobile phone network. 

Mobile broadband providers for consumers include Orange, BT, Vodafone, Three and T-Mobile. Business mobile broadband is offered by Vodafone and  T-Mobile.

N

Narrowband
Narrowband is another term for dial-up internet access. It uses a modem to connect with the internet via a phone line. Narrowband is much slower than broadband at around 57.6kb (compared to the the slowest broadband package speeds of 512kb). Unlike broadband, which can be transmitted down a phone line at the same time as a phone signal, narrowband monopolises a line - phone calls can't be made while someone is using dial-up to access the web.

You can view AOL's Anytime dial-up service here.

O

On Demand TV and Video
Broadband providers are increasingly offering on demand TV and video services via a customer’s broadband connection, to be watched by the user when they wish, rather than according to a schedule set by the provider. These on-demand services may be free, or pay-for.  Services include BT Vision from BT, which provides digital TV over broadband to BT Total Broadband users; Setanta Sports, with their Setanta by Broadband service offering live and on demand sports fixtures; and 4OD from Channel 4. On Demand TV uses a lot of bandwidth.

P

Packet
When information (a webpage, file or email) moves across the internet this information is broken down into tiny packets of information. These packets can be sent via different routes to their destination - this is more eficient as it can make up for different bandwidths along the way.

A packet is made up of the header (containing information about the packet); the payload (the data the packet is actually delivering); and the trailer (which marks the end of the packet and can also can check the packet has not been corrupted en route). The packet is moved along to its destination via routers. At the other end, the message is reassembled.

Podcast
A podcast is a pre-recorded digital file (usually audio)  available for download from the web, to be played on a computer or MP3 player. Podcasts are often distributed around the web via RSS feeds. Some podcasts are well-known shows recorded in a podcast format, while others are created specially and solely as podcasts.

The word podcast comes from broadcast and iPod, although podcasts can be played on non-Apple devices.

Q

Quad Play
Quad Play is a service currently only offered by Virgin Media. It is a bundle of four entertainment and communication services: broadband, TV, and landline phone delivered over a single connection, plus a mobile phone service.

R

Router
A router sits at a gateway between two networks and sends small packets of information across the internet to their next network points (where more routers will forward the packets on). Routers work out the most efficient route to send the packets by.

S

SDSL
SDSL stands for Symmetric Digital Subscriber Line. Unlike ADSL, where download speeds are significantly faster than upload speeds, SDSL is symmetric - data can be transmitted at the same speed both up and down the line. An SDSL line can only be used for data transmission (unlike a broadband ADSL connection that can carry phone and broadband on the same line).

SDSL needs high bandwidth availability. Such packages are robust but also more expensive, and as such are marketed at businesses which need reliable, tough broadband services.

SDSL providers include Eclipse.  

Softphone
This is a piece of software which lets you make phone calls via a computer using voice over IP (VoIP). Softphones can make calls to standard phones, mobile phones, and other some other softphones. However not all softphone applications can call other softphone applications. With a softphone you may dial a number using your keyboard or click numbers on a phone image on your screen.

Streaming
Streaming allows you to start watching a file (eg a film) before it has finished downloading to your computer, rather than having to wait for the whole file to download.

T

Traffic Shaping
At particularly busy times of day (usually between 6pm and 11pm) some broadband providers may prioritise traffic (eg busoness or VoIP traffic) or reduce traffic that is impacting on other users (eg originating from individuals who are particularly heavy downloaders) over their network. This is known as traffic shaping and is done to ensure the efficient use of available bandwidth.

Typosquatting
Typosquatting involves buying a miss-spelled domain name to take advantage of users accidentally typing in an incorrect brand or company name into a URL or search engine. A typosquatter can make money from this by placing adverts for other products on the site.

U

Upload Speed
The upload speed refers to the speed per second at which you can upload to the web. ADSL broadband packages have slower upload speeds than download speeds as most people with home broadband packages don’t need to upload much to the internet. This means that common upload speeds of 256kb are usually perfectly adequate, although some home broadband packages do have upload speeds of up to 448kb or even higher. Typically, business broadband packages will have faster upload capabilities.

Usage Cap
Usage cap is simply another term for a download limit. This can mean the advertised total amount of data you can download over a month with a given broadband package, or a special limit created by broadband providers to limit the downloading of a few particularly heavy bandwidth users. 

V

VoIP
Voice over IP (VoIP) involves making phone calls over the internet or a corporate network. VoIP is also known as Voice over Broadband, or Internet Telephony. The main benefit to VoIP is free or cheap calls to destinations all over the world.

VoIP packages may just need a microphone and speaker that you plug into your pc, and use with downloaded software (often called a soft phone). Other VoIP packages may have handsets or allow you to call standard phones.

VoIP users usually also need another way of calling as many VoIP packages do not allow emergency calls, or won't work during a powercut.

VoIP providers include Vonage and Skype.

W

Web 2.0
Web 2.0 usually refers to the second generation of web development and usage.

First generation web use mainly saw the world wide web as simply a tool to provide information to the user, or to sell products and services online.

However Web 2.0 uses the web as a collaborative and participatory tool in itself. Examples of Web 2.0 developments include the growth in social networking sites such as Facebook, Bebo and MySpace; the explosion of user-generated (and user-managed) websites such as Wikipedia; and the upsurge in niche and vertical sites rather than broad content sites.

Wifi
Wifi, or wireless fidelity, refers to the wireless standard IEEE 802.11. Wifi is used to create wireless networks. These use radio transmissions over short distances to create connections between devices without wires or cables.

With wifi you can use your laptop or other mobile device anywhere within your wireless network, or use public wireless hotspots if you are out and about.

Wireless Network
A wireless network uses radio waves to transmit users' requests from a wireless device to the internet using a wireless router. Each device (eg a computer, laptop, or PDA) will need a wireless adapter, though they now often have this functionality built in. You can however link several wireless devices to one wireless router.

With a wireless network you can surf the web from anywhere within the network's boundaries. However you should ensure it is secure as an unsecured wireless network can offer a way into your pc.

Many broadband providers offer wireless routers with their broadband packages - as a permanent part of the offer or as a special offer. These include AOL Broadband  and BT Broadband.

X

  xDSL
xDSL efers to all high speed broadband DSL, or digital subscriber lines (DSLs are characterised by the fact that they send data over the copper wire network). The DSL group includes ADSL (asymmetric digital subscriber line),  SDSL (symmetric digital subscriber line), and VDSL (very high bit-rate digital subscriber line), etc.

Y

Z

Numbers

3G
3G stands for third generation. Usually it refers to the third generation of wireless personal communications devices such as mobile phones and PDAs (hardware and services). 3G offers faster web browsing and mobile video, with the broadband "always on" even during voice calls. Apple iPhone is available with 3G.

Want to know more about broadband?

Check out our Broadband Frequently Asked Questions (FAQs) or Business Broadband FAQs. 

Who we are