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Broadband Jargon Buster

on 24 July 2013 - 7:12pm

Discussions about broadband always end up as comparisons of connection speed but what do we mean by "2 Megabits download" or "300 kilobits upload"?

Don't get your bits in a muddle, its actually pretty straightforward. Read on for a simple explanation.

Connection speeds are measured by the rate at which information can be sent over the wire. Digital information is encoded in "bits". Each "bit" of information is actually very small. Each of those "ones" and "noughts" that you've heard about is one bit. As you might imagine, you can transfer quite a lot of bits per second over a broadband connection, even one as slow as yours! Therefore we do the same thing with bits as the electricity board does with watts. One thousand bits is known as a kilobit (or kb), a million is a Megabit (or Mb).

So your broadband speed might be two Megabits per second (2Mb/s) now but in the future you may have fifty Megabits per second (50Mb/s), twenty times as fast.

Now, people usually quote their download speed when talking about broadband, however, upload speed is also important and most broadband packages provided by suppliers such as BT or Virgin are not "symmetrical". In other words the upload speed is much slower than the download speed. For instance, my upload speed is around 300kb/s (kilobits per second) or 5 times slower than my download speed of 1.5Mb/s (Megabits per second). This becomes important if you want to share pictures and movies or backup your files, or if you want to talk to your grandkids by Skype etc.

Got that? Ok, so there's an added complication, connection speeds are measured in kilobits or Megabits per second but those files that you might want to transfer are sized in kilobytes (kB) or Megabytes (MB), note the captial "B". A byte is 8 bits but to save yourself from having to work out things in 8s, you can round it up to 10. Therefore, if you have a 50Mb/s connection and you want to transfer a 50MB file, it will take about 10 seconds.

To give you and idea, five Megabytes (5MB) is about the size of 3 minute CD-quality song, 700MB is the maximum amount you can store on a blank CD. A DVD will hold about 4500 Megabytes (or 4.5 Gigabytes!) So to transfer one DVDs worth of information (such as a movie) would take almost 7 hours over my internet connection - it would be way past bed time by the time it finished! Over a 50Mb/s connection it would take just 12 minutes...

So now you know what it all means, why not check how fast your connection is? Visit the following site to find out your upload and download speeds click on the "start speed test" button.