How does a switch differ from a hub?

A switch operates at the Data Link layer of the OSI model and uses MAC addresses to forward frames specifically to the intended recipient device, creating a more efficient network by reducing unnecessary data transmission. This targeted forwarding capability contrasts with a hub, which operates at the Physical layer and simply broadcasts the received data to all connected devices, regardless of the intended recipient. As a result, every device connected to a hub receives all traffic, leading to increased collisions and decreased bandwidth efficiency.

The other choices touch on features that are generally true but are not the primary distinguishing feature between switches and hubs. For example, while switches do prevent loops through protocols like Spanning Tree Protocol (STP), this is not a defining characteristic that differentiates them from hubs in the same way that MAC address-based forwarding does. Similarly, switches can connect to multiple VLANs, but this capability is more advanced than what is typically considered in foundational comparisons; hubs simply lack the ability to segment network traffic at the VLAN level. Lastly, while speed can vary based on conditions, this is not a categorical difference, as not all switches are inherently faster than all hubs in every scenario; performance depends on specific models and network configurations.