I don't know why you keep counting two server side copies for each side. It's 4 total if both sides cache the file indefinitely and 2 otherwise. edit: Okay,

I don't know why you keep counting two server side copies for each side. It's 4 total if both sides cache the file indefinitely and 2 otherwise. edit: Okay, I see, you are talking about physical files. Sure then there might be up to 6 copies of the file.