Web Hosting Bandwidth

If you've been searching for a web host, you've probably encountered the issue of bandwidth.  Most experts agree that bandwidth should be a key consideration when setting up a website, but what exactly is it, and why is it so important?  In this article, we'll look at the whole issue of bandwidth, and outline some of the key things you need to be aware of.

What is bandwidth?

When a visitor clicks on a website, data is exchanged between the visitor's computer and the server that is hosting the website.  Bandwidth refers to the amount of data that each website is allowed to exchange with visitors each month.  In practical terms, it refers to the number of visitors that each website is allowed to receive. Web hosts set out the amount of bandwidth that each website can have in advance.  They have to do this, or risk their servers being overloaded by high volumes of traffic.

How much bandwidth, then, do you actually need?  Generally speaking, the more information there is on your site, the more bandwidth you will need.  If your site has lots of heavy media files, such as music, movies or animation, then you will need a lot of bandwidth.  A small site that is mostly made up of text and a few pictures will need much less.

You can perform a rough calculation to get an idea of the amount of bandwidth you will need.  Look at the average size of your website pages, including all of your JavaScript files, embedded images, external style sheets and so on.  Add that to the size of any files that you want people to download or view on site, such as Flash movies.  Multiply that by the number of visitors you would like to get per month, and add a little bit more for things like email exchanges and file transfer.  This will give you a number in mega-bytes, which can act as a guide to the sort of bandwidth your site will need.

Most web hosting companies are very upfront about the amount of bandwidth each user can expect to get.  However, bandwidth allocation is not without its risks.  A recent practice is the overselling of bandwidth allocation.  This is similar to the airline practice of overselling seats.  Airlines know that some passengers just won't turn up, and in the same way, web hosts know that a lot of sites won't use anything like the amount of bandwidth that they're entitled to.  Just as airlines run the risk of all the booked passengers turning up at once and not having enough seats for them, web hosts run the risk of all their users taking up their allowances and overloading the servers.

An unexpected surge in traffic can also cause your website to crash.  If you suddenly get a lot of visitors, perhaps because of a link from a popular website, your hosting company might bill you for exceeding your bandwidth allowance in that particular month.  They might even shut down your site completely if this happens.  Web hosts have also been known to "throttle" traffic, preventing visitors from reaching your website, to avoid overloading bandwidth at certain times of the day.