Bandwidth in the dedicated hosting environment

What does bandwidth mean?

When searching for hosting for our web site we will frequently read the word bandwidth. In basic terms they are talking about the amount of data that they allow us to transfer in a period of time. In most of the cases this period is a month. If we use a dictionary to define bandwidth we will find the following definition:

Bandwidth: Data transfer capacity of an electronic communication system. Maximum transference rate of this system.

Bandwidth in the hosting enviroment

When surfing a hosting web site we will find some text that indicates to us that, for example, they allow us a bandwidth transfer rate of 5 Gigas of bandwidth per month for an specificic dedicated hosting plan. In other words, we will be able to transfer 5000 Megabytes of data per month from our site. Usually if we surpass this amount of bandwidth we must pay an extra amount for each additional Giga consumed.

It is important to stand out that the bandwidth is used every time a person visits our site. Each time an image or a document is loaded we are using bandwidth that will be discounted from the monthly total which we have assigned. Therefore we must consider all the files that take part in the visualization of a web page and not only the specific document (no matter this one is html, php, asp or any other).

In the design phase of our web site it is really advisable to optimize at maximum all its components, specially the graphical files, where we will be able to save great amount of our bandwidth. It turns out quite simple to calculate the total transfer when a user visits our site. The following is an example:

Home page total size: 10 KB

Total number of images: 10

Total combined size of images: 75 KB

Total visitors: 1

In this example, by each person who visits our web page 85 KB of data are transferred only when loading the home page. This does not include when surfing through the rest of our site. If an intensive promotion is made and we begin to receive approximately 500 daily visits, making the calculation, 85 x 500 KB = 42500 KB (42,5 MB) of data transferred by our home page per day.

We could also make a more realistic estimation if we calculate that each average user visits 2 pages aside from home page before leaving our web site and we would therefore have an approximated transference of 150 MB daily. Then we could estimate 4,5 GB bandwidth monthly and decide that a dedicated server that allows us a consumption of 5 GB monthly would be suitable for our present requirements.