Question : Excess traffic charges with abnormal upload/download ratio

I have a client who has been hit with an excess traffic bill of over $20k over 3 months.  They have had some trojan activity, which I thought was to blame, but there are a few discrepencies...

1. On days when noone was in the office consuming traffic, the upload/download ratio was weird if not impossible. eg: 8GB downloaded, less than 1MB uploaded.
2. On days that the traffic usage was high, it was exactly 4.1GB (or multiples there of) above the norm.  That's odd.

My quesiton is... is it possible to download 8GB of data and only incur 1MB of uploads? And if it was virus/trojan activity, why (unless there is an error in the bill) would each occasion be the same quantity of download?

Answer : Excess traffic charges with abnormal upload/download ratio

To actually answer your question, YES it is entirely possible.
With Azureus (P2P software) I can indeed tell it NOT to upload but only download.
(Small acknowledgment packects get sent)
I'm sure that option is available in almost all P2P style programs.
I can also tell it to limit it's bandwidth and also how much it downloads in a day/chunk.
You get the idea.
It's entirely possible and I'm leaning as you can gather the same way rindi did.
p2p (Or FTP cos that can be done too) software thats just been told how much to get.
If it's a subsurive thing they will tell it to start when no-ones at work in theory. Can the ISP tell you when the usage spikes? (Or if it does)

Terry