I'm suspicious that that IP address isn't random at all!
Interestingly enough, the author himself uses the word "random" to describe the address, but then implies it is indeed unique: "it didn't resolve to anything".
I believe he really meant "unknown" there, but he is a professional researcher, so what do I know? I guess we will have to wait for the paper he mentioned he was writing on the subject.
http://www.thefreedictionary.com/random
> 3. informal (of a person) unknown: some random guy waiting for a bus.
It's not great journalism, but this is the register.
But it's needlessly confusing to use "random" to describe something that's represented numerically unless it's mathematically random. "Arbitrary" or "unknown" is better.