The network. It's that simple. It will not tell much more than that. Since porn is such a high percentage of internet traffic (read http://www.bbc.com/news/technology-23030090 ) then unless you are in China or such a country I wouldn't worry too much.
Maybe the title doesn't give the right idea but I am at a loss to explain my question in 60 characters!
I have living space that I rent out & those people have access to internet via an extender that wifi's from my router.
They can't log into my router but I give them a key for the extender.
The person currently renting the space is (I think) downloading porn at night on his ipad because my nightly data volume usage has gone way up.
What IP registers when someone accesses the net via a wifi extender?
Is IP the correct name for the address of the downloader? I'm not sure if I have that right.
Does the address of my router get broadcast to the porn company or is it the address of his ipad?
I really have no idea as I have never accessed porn.
And I certainly do not want any association to come back to my gear, my internet provider or connection.

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