Maybe a more efficient updater and LAN games?

I was wondering if the updater uses the differences of the files that are updated and reflects the changes of the files locally instead of downloading an entire new file every time? This is completely based off guessing on the size of the updates for lol. I realize that there are updates to visuals and what not, so that is going to skew this guess. Just out of curiosity and those of us who wait two hours to play lol.

Also, something that would be really cool for people with satellite internet is to have the ability to create a local game with a lol server running on the LAN(Local Area Network). So the client would connect to a local sever on my home network without being connected the World Wide Web and be able to play with just that server. Plus that would be super fun with the really low ping :). Then we could just play our friends if we don't have access to great high speed internet and still be able to play lol.