During a review of her organization's network, Evaggelia discovered that it was suffering from broadcast storms and that contractors, guests, and organizational administrative staff were on the same network segment. What design change should Evaggelia recommend?

Network segmentation can reduce issues with performance as well as diminish the chance of broadcast storms by limiting the number of systems in a segment. This decreases broadcast traffic visible to each system and can reduce congestion. Segmentation can also help provide security by separating functional groups that don't need to be able to access each other's systems. Installing a firewall at the border would only help with inbound and outbound traffic, not cross-network traffic. Spanning tree loop prevention helps prevent loops in Ethernet networks (for example, when you plug a switch into a switch via two ports on each), but it won't solve broadcast storms that aren't caused by a loop or security issues. Encryption might help prevent some problems between functional groups, but it won't stop them from scanning other systems, and it definitely won't stop a broadcast storm!