We are often asked about Broadband “speed” and, in particular, whether anything can be done to improve the (download) speed to home users. This article does NOT apply to “Cable” Broadband delivered by VirginMedia in the UK. It might be helpful to firstly explain what Broadband is and how it works. Broadband (also known as ADSL) got it's name from the term "broad bandwidth". Broadband allows users to connect and use the internet and the telephone simultaneously on the same telephone line so both can be used at the same time without interrupting the other; the telephone voice and Internet data are separated by using a microfilter.

Your computer will be connected to a broadband modem or a router (if you want to connect more than 1 computer). From the router, you will plug into a microfilter which has 2 sockets: one for the cable going to the modem/router and one that the telephone plugs into. The microfilter is then plugged into the telephone socket. In it's simplest form, that is all you are likely to physically see within your home/office for your broadband connection.

When you set up broadband, it is important to make sure you add a microfilter to all the phone sockets that share the same line as the broadband connection (even if they do not have any physical connected between that socket and the modem/router). You will find that, unless you have these on all the sockets, then if a call is made or received, the broadband connection will get interrupted. Adding microfilters to all the phone sockets will mean that the broadband continues to work even when calls are made or received.

To test current download speed, go to the “BT SpeedTest” web site (www.speedtest.bt.com) and follow the on-screen instructions to see test results.

Note 1:
DSL Connection Rate (DOWNSTREAM) - this is the speed of the connection between your property and the BT telephone exchange.
IP Profile - this is the fastest speed you can currently get whilst also receiving a stable connection. This should be just under your DSL Connection rate.
Download Speed - the actual speed at which you are downloading. This should be close to but never higher than the current IP Profile.
In ideal conditions, the download speed will be just under the IP Profile. If there's a considerable difference, check as many of the things shown  below before reporting this to your Internet Service Provider (ISP).

Note 2: This test can be carried out about once an hour. Use other Broadband speed testers in between such as http://www.speedtest.net/

Why do I need to do this?
If your ISP reports a broadband fault to BT Wholesale (also known as Openreach) and an engineer finds your equipment or settings are the cause, you'll be charged for the callout.

Check your internal network and hardware
If possible, try a different router or modem on your line. If this fixes the problem, your hardware is faulty and needs replacing

Make sure your telephone line is working
You'll see problems with your broadband if the telephone line isn't working properly. Pick up a telephone handset and check for a dial tone. If the line sounds clear and you can hear a dial tone, see ’check your microfilters’ below. If the line is noisy or you can't hear a dial tone, you should report the problem to your telephone provider

Check your Microfilters
Broadband shares the line with your telephone service. Microfilters separate the signals and prevent one from interfering with the other. Subsequently, anything connected to your line needs to pass through a microfilter. If you have spares, change the microfilter adjacent to the router, and others one at a time, checking the speed each time you swap one to eliminate them from the equation.  If your microfilters are fitted correctly and your downstream rate is still low, see ’test from the master socket’ below.

Test from the master socket
Make sure your extensions and cabling are OK by testing your broadband in the master socket. You'll find it at the point where the telephone line enters your property. Most look like the picture left.

Ideally, you should take off the front plate by removing the two screws and ease the plate towards you. The wiring to any phone extension sockets may be attached to the plate so move it very carefully - see picture below right

To test, unplug everything from your line (including any TV set-top boxes, other telephones and all microfilters) and connect your router to the master socket (through one microfilter) connected to the test socket inside the Master Socket - see picture below left. If the downstream rate increases, either your extension wiring or something connected to your line is causing the problem. Find out which by checking after plugging each piece of equipment back in. Try replacing your microfilter(s) if you can't find the culprit. If the downstream rate remains low, see ‘try a different router’ below.

Try a different router
If you can, try a different router or modem on your line. If the downstream rate increases, your current router is faulty and needs replacing. If the downstream rate remains low, your current router is fine and it could well be that a call to your ISP is required.