Final answer:
Example Corporation is using the network security concept known as network segmentation to separate different parts of their network for increased security.
Step-by-step explanation:
The concept Example Corporation is using for their network security by splitting their network into zones such as sales, HR, research and development, and guest networks is known as network segmentation. This approach enhances security by controlling access to various parts of the network, essentially creating barriers that confine possible security breaches to a single zone, rather than allowing them to propagate throughout the entire network. By segregating networks, it limits a cyber attacker's ability to move laterally across the organization's network.