Blizzard Entertainment is a video game designer and publisher headquartered in Irvine, California. They are most famous for the wildly popular World of WarCraft (WoW) and Diablo game series. Blizzard Entertainment is a division of Activision Blizzard.

Wow uses a modified BitTorrent protocol for downloading the client. A router is a physical device that allows you to share your internet connection between multiple computers. Most routers will not allow incoming traffic to your computer unless you have configured them to forward the necessary ports to your computer. The Blizzard Downloader requires that TCP and UDP ports 3724, 4000, 6112, 6113, 6114 and 6881-6999 be forwarded.

This SonicWALL signature can detect and prevent World of Warcraft (Wow) SSL Certificate for *.battle.net domain over any TCP port.