The Download Filter is a list of file extensions that the administrator can allow or deny the users from accessing while they are surfing the Internet.
By default, the Download Filter contains the categories of images and layouts. The reason for this is that some websites retrieve image files and layout files from external websites or servers. In order for the website to look properly, the Download Filter will allow the images and layout files on the website to be loaded without being blocked even though the files are not on the Allowed list.
In contrast, you can put files extension on the Download Filter that may be a threat to your network. By adding .exe, .zip, .tar and etc. files on the Download Filter, you are preventing users from downloading those files.
The streaming of audio and video files can also be blocked by putting in the appropriate file extension, such as .mp3, .swf and .mpeg.
There are three permission types. When “Allowed” is selected, the file extensions in the category will be allowed. When “Blocked” is selected, the file extensions in the category will be blocked. When “None” is selected, the file extensions in the category are not active and will be ignored.