Bandwidth is a measurement of data transfer rate expressed as a unit of digital information divided by a unit of time, such as 200 bits per second (a bit is a single digit — either a 0 or a 1 — in binary code). If you own an ecommerce business, the data for the front and back ends of your shopping cart must be stored (hosted) on a server. As you and your customers request specific pages associated with your site, the server transmits the data to your web browsers; this data transfer consumes bandwidth. It is vital to remember that a server’s bandwidth capacity is dictated by the physical properties of its network connection cables (think of them as water lines, which cannot pump water beyond a specific maximum rate). This means that bandwidth is a finite — and valuable — resource. When a server receives more requests than it can fulfill at once, it must slow down, delay, or deny some requests. And, yes, even hosting that offers “unlimited” bandwidth is not exempt from these basic limitations.
Since most hosting companies assign multiple clients to a single server, any individual client’s bandwidth consumption can affect all other clients sharing the server (think of water pressure dropping when too many faucets try to draw from the same water line at once). Therefore, the hosting company must allocate a certain acceptable amount of the server’s total bandwidth capacity to each client, usually a monthly rate specification. This allocation is based on the client’s level of financial commitment, which in turn is based on the client’s anticipated needs. If you use more than this agreed-upon bandwidth allotment, you can expect to pay overage fees.
Here are some conversions that will help you anticipate how much bandwidth you can expect your site to consume:
1 Byte = 8 bits
1 KB = 1024 Bytes
1 MB = 1024 KB (1,048,576 Bytes)
1 GB = 1024 MB (1,048,576 KB / 1,073,741,824 Bytes)
-David Yakubik, Volusion