If he's downloading the file, he's pulling it. For your ISP that's outgoing traffic. You didn't tell how your ISP calculates the bandwidth you use (only incoming traffic: from the internet to you) or also outgoing traffic (from you to the internet). So, lacking that formula, it's impossible to say what would happen.
Kees
My second external Iomega 1 TB HD is arriving this afternoon, and I've been thinking about using some of it as a file server (mostly video) for family and friends all over the US, and even a couple in the UK.
Trouble is, I don't really know how a server works, but I guess I need to start with 'OS X Server' from the Mac App Store. My main concern is whether someone downloading a file to their computer is going to suck up all of my precious little internet bandwidth or not. So let me ask the question this way; if my brother in Half Moon Bay, CA is downloading a file from my server in Ann Arbor, MI, is his PC pulling the file, or is my Mac pushing it?
Since I don't want to turn this project into a career, are there any other concerns, I should look out for?
Thank you.

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