Google has made it easier for I.T. admins to deploy updates to Chrome OS devices while reducing broadband consumption at the same time. The approach involves P2P, or peer to peer, connections.
Beginning with Chrome devices on Chrome version 40 or later, when possible, Chrome devices will use a peer-to-peer (P2P) auto-update behavior that allows faster update of Chrome devices from nearby devices instead of downloading the update from Google's servers or an intermediate caching proxy, if you have one set up. If peer-to-peer auto-updating fails or is not possible on your network, devices will update through normal channels.
The premise here is that there's no need for every deployed device to individually download the software updates over a web connection. Instead, updates already downloaded and installed on one Chromebook or Chromebox can directly provide the new software to another.
Google notes that a full Chrome OS build is typically around 400 MB while updates are generally around 50 MB. You can't deploy a full build from one machine to another but even a bandwidth savings of 50 MB per device for updates can add up quickly depending on the number of Chrome OS devices in a location.