I too work for a large company that rolled out Kontiki. Like the previous poster mentioned Kontiki is a commercial, enterprise class BitTorrent like tool. We also use it to deliver video to the desktop. I havn't worked directly with those guys for years but believe you could use it for most any type of content. I believe they can handle your security needs as well as dynamically adjust how much bandwidth they are using based on a number of different criteria. I'd give them a call to at least inquire further.
http://www.kontiki.com/
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I too work for a large company that rolled out Kontiki. Like the previous poster mentioned Kontiki is a commercial, enterprise class BitTorrent like tool. We also use it to deliver video to the desktop. I havn't worked directly with those guys for years but believe you could use it for most any type of content. I believe they can handle your security needs as well as dynamically adjust how much bandwidth they are using based on a number of different criteria. I'd give them a call to at least inquire further. http://www.kontiki.com/