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Beginners FAQ

How much am I downloading?

With the introduction of broadband packages that have download limits in place, it is useful to know how much you are downloading. Use tbbMeter, our free tool, to help you keep track.

A number of ADSL routers will also record the amount of traffic passed, which is useful if you have two or more machines. Some ISPs can also inform you of this information if you use their products. Additionally the USB & PCI modems which use the Windows Dial Up Networking system will display the number of Bytes you have downloaded.

You can also estimate your usage if you know roughly what you do with your connection, for example:

The ISPs often display the limits generally in GB which is a GigaByte. A GigaByte is actually 1024MB (MegaBytes).

Which is better, IPStream or DataStream?

Neither IPStream nor DataStream is 'better' necessarily. These are both BT Wholesale provided services but they deliver the connection to the ISP in a different way.

IPStream is a service where the user traffic is routed longer inside BT's managed network whereas with DataStream, the ISP takes one or more 'virtual path' (VP) circuits to each local exchange so they can manage contention themselves.

Most ISPs use DataStream to deliver services with high contention ratios spread over very small numbers, so often DataStream will deliver worse performance, however technically it is capable of more customised services, including 1:1 contention. Therefore, you should not choose a service solely because it uses IPStream or DataStream but look into user experiences of the particular service. DataStream's advantage in the current market is for ultra low cost services, or low contention / uncontended services and where Quality of Service (QoS) is needed.

Can I have ADSL on a line with BT RedCare?

Yes. Since August 2003, the standard RedCare service from BT is available on ADSL lines, although there are some caveats and restrictions. More information can be found on the BT RedCare website here.

I have a Mac - Can I use ADSL?

Yes. Customers should buy a modem which supports the Mac or a Wireless or Ethernet router. If your ISP supplies a modem for you, check for Mac support before ordering.

How long is the contract?

Contract length varies from product to product and ranges from 1 month upwards. Use our search to filter by contract length. Some service providers may offer longer contract periods in return for lower charges.

If signing up to a service with 'Free Activation' we recommend checking the terms of this offer if any exist. Some providers require repayment of the activation fee if you leave within a variable time frame, and this can be a different period to the main service contract.

I'm not a BT customer - Can I have ADSL?

If the telephone line to your property is actually installed and run by BT then you should be able to have ADSL (subject to survey). There are providers now where do not pay BT directly, so it is not always obvious, whether the line is a BT line.

LLU (Local Loop Unbundling) which is a rapidly growing area will mean that ISP's can offer you the service and will allow BT to be bypassed, this is still relatively new and is being used to get very high speed broadband services of up to 24Mbps out to people, way before BT is able to. You may be able to get broadband through a cable modem however which uses the local cable providers network rather than the BT telephone network. This offers similar speeds and services.

In addition to the fixed line services, like ADSL and cable, there is a growing number of wireless providers, which can either be fixed to a specific address due to the antenna, or used fully mobile.

What does contention mean?

Please see our contention page.

What can I do with it?

A simple answer to this would be: Anything you already do with your 56k connection just much faster. However, you can do things that wouldn't be viable on a dialup connection:

NB: Users may experience issues using certain services when using NAT on their router. (For further info, please visit our NAT FAQ).

Do I still have to pay BT line rental if I get ADSL?

Yes. BT's telephone billing (line rental and call charges) are unrelated to your ADSL. You will however not have to make any calls to the Internet as the ADSL is an always-on connection.

Though there are some exceptions, since there are telephone providers who will pay BT on your behalf, i.e. the telephone line is still BT owned but you can pay for it via a third party. If you are on a fully unbundled line, then you will not be paying BT any money. Most unbundled providers use shared lines, where BT still provides the telephone service, so rental will continue to be paid to BT.

How does it work?

The service makes use of your existing telephone line. It splits the signal into two channels, one for voice communications and the other for the high speed data communications. It makes use of a frequency range not used in normal voice communications:

Voice: 0 - 20 kHz
DSL: 25.875 kHz - 1.104 MHz
ADSL2+: 25.875 kHz - 2.208 MHz

Graphically, it looks like this:

Khz 0 20 40 60 80 100 120 140
PSTN <---->
ISDN <--------->
ADSL <----------------------- upwards to 1.104 MHz
ADSL2+ <----------------------- upwards to 2.208 MHz

For a detailed explanation, click here.

Who offers ADSL?

Many ISPs offer an ADSL service, see our ISP list for details.

What is ADSL?

ADSL is a broadband connection technology which utilises existing copper wired telephone networks. ADSL uses a wide range of frequencies over an existing telephone line to deliver much higher speeds than your standard 56k modem (between 10 and 140 times faster). It is also possible to use your phone while online. See also: Beginner's Guide

What is the difference between ADSL and DSL?

ADSL is a type of DSL where the upstream and downstream speeds differ (hence the "asymmetric" part). There are many variations of DSL technology for different types of application (HDSL, SDSL, etc).

What does ADSL stand for?

Asymmetric Digital Subscriber Line.