Bandwidth, measured in megabytes (MB), is the maximum amount of data that can be transferred in a certain period of time - as it applies to Host-A, one month. If you had a 10 MB file and 510 MB of bandwidth, that file could only be downloaded 51 times. It could not be downloaded again until the bandwidth resets to its original value - here at Host-A it is the first day of the coming month. Related topic: storage space.