Area-of-Interest-Based Data Sending/Receiving

Because my game has so much data to process for each player, and there are lots of RPCs to be sent out, I was hoping to implement a system where clients only receive information from the server if that information is relevant to the region they're currently in. Something along the lines of THIS. So this bring two questions to mind.

1. Is this possible with the current capabilities of UNet?
2. If so, where would I begin to look in the docs for it?

 

As far as built-in implementation in UNet, I doubt it exists yet (but I'm pretty far behind on the whole UNet thing). Even though it might not be available in UNet, it's probably not that difficult to implement, especially since UNet is much more feature-rich than the legacy system -- if it's not possible to implement it in the High-Level system (which I'd doubt), the Low-Level system will definitely allow you to.
UPDATE: SeanR just posted the NetworkProximityChecker; it's a UNet supported system of what you want.

 

Much obliged @seanr ! Complete oversight on my part.