it's basically the "Node" function in Logic.
you can use multiple Mac's, connected via Ethernet, to give more CPU horse power to run Logic.
however, you can only use it on Logic program and its plugins. can't use Node on 3rd party plugins.
so say if you have Waves Linear Phase EQ, which is a CPU hog, you can't use a separate Mac to process the LP EQ. you can, on other hand, distribute whatever plugins Logic is using to other Mac's connected, then you can use host computer to run LP EQ.
IME tho, using Node creates a certain lag or delay in audio; so it's not quite up to snuff.
you can use other progams that can do similar thing. IIRC, it's called Wormhole.