Update accelerator
Take a look at IPFire update accelerator and clone it, it caches windows updates, antivirus, common regular updates, even android and iOS updates. It’s one functionality that is handy saves bandwidth, time and it is a lot better than managing and hacking proxy settings.
Info:
http://wiki.ipfire.org/en/configuration/network/update-booster
http://blockouttraffic.de/ua_index.php
http://forum.ipfire.org/viewtopic.php?t=12868
From forum post https://www.clearos.com/clearfoundation/social/community/what-features-or-changes-would-you-like-to-see-around-here#reply-250921
Edited by Nick