Although the HTTP download allows for only one file to be selected for download at a time, it is a browser controlled download, and as such does not use the Java Runtime Environment or require the installation of any applets on your computer. The HTTP download uses HTTP 1.1 allowing browsers to resume an interrupted download in most cases. This method does, however, require that cookies be enabled, to transmit an encrypted hash code to the download server. Without this code, your download will fail.
If you wish to begin downloading multiple files at the same time, this method allows you to select as many files as you wish, begin the download, and go on to other areas of business. The process requires that a Java Applet be installed on your machine that manages the download process, so that when one file completes it's download, the next in the queue is initiated. It also allows for the use of the "Resume Downloads" feature on the web site. We recommend the use of the Java Runtime Environment (JRE) version 1.4.2 as there is a bug, documented on the Sun site, between Verisign certificates and certain other versions of the JRE. This bug will still allow the download, but a warning will appear stating that it is not a trusted source.