Ironport WSA "rangerequestdownload" option

[fred.sorrell]

  Where can I find more information about "rangerequestdownload" option on the Iron port WSA appliance? I've googled the topic, and did not find much information. I need to determine the security ramifications for enabling this option.

[Erik Kaiser]

Hi Fred,

Rangerequestdownload allows the WSA to request an object in chunks versus trying to download the entire file each and every time the client makes a request for just a small portion of that entire file. When the WSA does not use rangerequestdownload and a pc requests to download a 1GB file the pc will actually request it in pieces. Now everytime that request is made by the pc for another piece of the 1GB file the WSA will request the entire file rather than just the small part of the file that the PC has requested. This will actually either be very slow or can cause failure to download the file. The problem with enableing rangrequestdownload is that as the file is broken up into pieces it eliminates our ability to scan the file to determine if it has a virus / malware signature in it. This will increase the chances of malware or a virus slipping through the WSA unless WBRS scores the URL your trying to download the file from with a -6 or below thus blocking the download all together.

Sincerely,

Erik Kaiser
WSA CSE
WSA Cisco Forums Moderator