By default Internet Explorer allows to download only 2 files simultaneously. To download another files, user has to wait while previous downloads finishes. Due this IE limitation downloading may sometimes become quite inconvenient, especially with high bandwidth connections.
For example, imagine a many volume archive or several quite large video clips. While download first two of those files, it will be impossible to start downloading next ones. The user will be forced to manually run each download process after previous one finishes.
Adding more concurrent download streams allows to facilitate file downloads and in most cases it is possible to forget at all that there are quite a number of downloads actively processed by Internet Explorer. This allows to save human time and pass requests for downloads to IE whenever there is a need!
Please do not hesitate to contact our support department with any possible questions regarding IE download streams.