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Cable vs. DSL
What is broadband?
Broadband is term used to describe a device that uses a wide range of frequencies. The amount of frequencies that can be carried on a signal is directly proportional to the amount of information that can be sent. A video signal has many more frequencies and a much larger amount of information than an audio signal. Broadband devices such as Cable and DSL modems are capable of receiving much larger amounts of data because they handle a much "broader" range (band) of frequencies (Broadband).
Download and Upload
Download, sometimes referred to as Downstream speed, is a term used to describe the speed at which your computer is able to acquire information from the internet. Downstream speed is a general benchmark of the internet service. The service compete in terms of offering the faster download speeds in terms of megabits (Mb) per second. Note that 1 Mb is not 1 megabyte (MB), 1 Mb is 128 kilobytes (kB) which means that there are approximately 8.5 Mb in 1 MB. The larger the download speed, the faster you will be able to download files form the internet.
Upload, or Upload speed is generally a term used to describe the speed at which your computer is able to upload the information to the internet. Although it isn't as obvious as to why users need upload, it is a very important component of your connection to the internet. Whenever you log on to a web page or send a password to log on to your email account, you are uploading. While the information that you upload is almost insignificant compared to the information you download, it is still there, and without it you would only be able to accept incoming information, but not have the ability to request information.
How DSL works
The general idea behind DSL is as that human voice travels along the the telephone lines at the frequencies lower that 4000 Hz or 4 kHZ. The lines, however, can handle much broader frequency range; so if you were to put a filter on the telephone to filter out all of the unnecessary signals, you could jam all kinds of frequencies through the wire without interfering with the person that is talking on the phone. The upper frequencies are divided into subsections of approximately 4 kHz each some of which are reserved for downstream while the others are reserved for upstream. DSL usually limits at around 24,000 kB depending on the cables of in your local areas.
The internet signal from your computer is encoded by your modem into a digital signal and then sent over by telephone lines to your internet service provider. Since the framework of the telephone lines is already implemented