Easton (The Quince Man Quincy) Royce

What is a kilobit?

A kilobit, (represented by a capitalised K and a lowercase b “Kb”) is 1 of 8 bits, that make a byte. Every byte contains 8 bits.

What is a kilobyte?

A kilobyte, (represented by a capitalised KB) is a culmination of 8 bits together to make a byte. You may have heard of “normal bytes” and real “bytes”. A normal byte, is usually a normal number, like 1000. A real byte, is the actual calculation of all the bits in the byte (1024).

Normal bytes and real bytes often get mixed up, which is often the reason why people get confused when someone is talking about real bytes and the other is talking about normal bytes, and neither knows what the other is talking about.

The Official Measurement

The official measurements are:

1 (one) Byte = 8 bits
1 KiloByte = 1024 bits
1 Megabyte = 1024 Kilobytes
1 Gigabyte = 1024 Megabytes

So How Do I Work Out My Maximum Download Speed?

Working out your maximum download speed is quite a simple process. All you do is take the number (the speed of your internet connection) and divide it by 8. For example, so you connect to the internet at 42Kbps. You would use the following calculation:

42 / 8 = 5.25KBPS.

This is the maximum possible download speed. Use the guide below.

14.4 Modem Connection – 1.8KBPS (KiloBytes Per Second)
28.8 Modem Connection – 3.6KBPS
33.6 Modem Connection – 4.2KBPS
57.6 Modem Connection – 7.2KBPS

NOTE!: 57.6 is normally referred to as 56 (For simplicity sake), therefore having a download speed of 7KBPS.

As you can see, the same rule can be applied for any speed connection. For example, I use a 1.5Mb (Megabit) ADSL connection to the internet. So my maximum download speed is 1.5 divided by 8 or 1024 multiplied by 1.5 and then divided by 8. This gives a maximum download speed of 192 KiloBytes per second.

Naturally, all downloads do not occur at this speed, often they are much less, and are often dependent on the upload speed of the server the download is coming from.

Some broadband connection speeds are calculated below. These can be applied to ISDN, ADSL, SDSL, Cable & Satellite.

64 Kb (Kilobits) Connection – 8KBPS
128 Kb Connection – 16KBPS
256 Kb Connection – 32KBPS
512 Kb Connection – 64KBPS
1.0 Mb (Megabit) Connection – 128KBPS
1.5 Mb Connection – 192KBPS
…
And so on.
…
…
…
4.5 Mb Connection – 576KBPS

In order to be downloading at 1 MB (Megabyte) per second, or faster, you need to invest in a very high speed connection.

10 Mb Connection – 1280KBPS or 1.28 MegaBytes Per Second.

All these speeds are theoretical, more so then actual possibility. Even with dialup, it is often hard to be able to download at the possible maximum. Regardless of your connection type, the same calculation can be applied to find out your theoretical maximum download speed.

However, you are always limited by many factors including:

Line Interference (Noise)
Line Availability
Drop Outs (Cable, *DSL & Modem)
Internet Traffic (other users, not to mention all the junk email)
Availability of Servers
Other users accessing the same content
Your ISP.

written by Easton Royce \\ tags: Networking, Support