What device is used to connect LANs that are separated by great distances?

To connect LANs that are separated by great distances, a router is typically used. Routers can manage traffic between different networks and facilitate communication over long distances, often utilizing various types of connections such as leased lines, fiber optics, or even wireless links. Additionally, VPNs (Virtual Private Networks) may also be employed to securely connect remote LANs over the internet.