Data Cap Limits - Serviio Question

So I'm setting up a home network and Serviio works wonderfully with my XBMC setup. My issue is that my internet provider caps data usage at 250GB per month. I'm completely new to this, so this may be a stupid question. Since Serviio essentially runs from my own computer and streams to XBMC, does that actually count as data usage on a internet plan? I suppose what I'm asking is if the data transfer between the two is just purely internal to my network, or is this essentially the same thing as streaming from an external site (as far as my internet service provider is concerned).
Again, sorry if this is a stupid question. I can't get the answer anywhere!
Again, sorry if this is a stupid question. I can't get the answer anywhere!