The actual speeds you experience day-to-day depend on many factors, such as your distance from the telephone exchange and general congestion on the Internet.


The speed of both your computer and your broadband connection can be adversely affected by spyware, adware and viruses.


Many factors influence your actual broadband speed, including the quality of your household wiring. Did you know that electrical devices like microwaves and even Christmas lights can interrupt your broadband service?


Your connection speed (or ‘line rate’) is the speed of your phone line between your router or modem and the local exchange. It is determined principally by the length of your line and its condition. (Note that old wiring is more susceptible to interference and faults.)


However, the speed at which you see web pages or download files is determined by more than just the speed of your phone line – this is also governed by the speed of your computer, congestion in BT’s or your ISP’s network and in the Internet, and speed of website servers.


This end-to-end speed is measured by ‘throughput’ speed - the actual rather than maximum speed your data is travelling at in given moment. Throughput is the speed reported by most online speed-test websites eg. adslguide. It is normal for your throughput speed to reduce significantly between 5pm and 10pm daily, as this is the time when BT or your ISP’s network and Internet congestion is at its heaviest.


No wonder the industry feels like a closed shop that too often blames the familiar failings of ADSL. BT Wholesale asserts that the download speeds to your home depend on at least nine often imponderable factors. They include your distance from the exchange, your ISP’s investment in its network, the local weather, the location of the site you are accessing and how well “the internet” is performing that day. Poor internal wiring,  electrical noise and low quality hardware can all affect the performance.



“Up to” nine imponderables? Nine ready-made don’t-blame-me excuses that your ISP, or BT Wholesale, can invoke. The ISPs use the technical limitations to hide speed restrictions on their networks then blame  slow speeds on the ADSL technology or other aspects of equation, such as distance. TalkTalk, for example used such an argument to explain why few of its 8-meg customers were receiving a faster service than its 2-meg subscribers.


Don’t even raise the topic of “traffic-shaping”, a means of either forcing too many customers over limited bandwith or throttling speeds for bandwidth hogs, especially peer-to-peer file-sharers. Few ISPs want to tell you about this dark art. Nearly all ISPs are shaping traffic in one way or another.


With so many factors influencing the delivery of broadband, the performance of any ISP inevitably fluctuates wildly from month to month. . Be Warned: Following the herd to the cheapest or most popular offer only leads to frustration.    



You can test the speed of your broadband  by carrying out a speedtest (for example, at http://speedtester.bt.com).