A lot of the PS4’s nifty capabilities will require an internet connection. Obviously, streaming requires an internet connection. Jumping into your friend’s game requires an internet connection. Using Gaikai’s stream while you download service requires an internet connection. Heck, downloading anything requires an internet connection. This has led many to believe that the PlayStation 4 will require an always on internet connection in order to operate. Fortunately, this is not the case.
Eurogamer has confirmed that the PS4 will not feature any sort of always on internet connection-DRM or otherwise. In a discussion with Sony’s Shuhei Yoshida, Eurogamer confirmed that the PS4 can go totally offline if that’s what you’re in to. “You can play offline but you may want to keep it connected,” Yoshida said. “The system has an [optional] low-power mode - I don't know the official term - that the main system is shut down but the subsystem is awake. Downloading or updating or you can wake it up using either the tablet, smartphone or PS Vita.”
So all of these capabilities are, in fact, totally optional. You can use your PS4 as a simple game-playing device and nothing more. Of course, then you are missing out on a lot of what makes the console cool.