What key feature differentiates a managed switch from an unmanaged switch?

A managed switch is differentiated from an unmanaged switch primarily by its ability to be configured remotely. Managed switches offer advanced features such as VLAN support, Quality of Service (QoS) configurations, network monitoring, and the ability to create secure network segments, making them ideal for complex and large networks that require a high level of control and customization.

This remote configurability allows network administrators to adjust settings based on the needs of the network, enabling better performance tuning and troubleshooting capabilities. In contrast, unmanaged switches are typically plug-and-play devices with no such configurations available, making them suitable for simpler, smaller network setups where extensive management is not required.

The other options, such as cost, port count, and speed of data transfer, can vary widely among both managed and unmanaged switches and are not defining characteristics for their differentiation. Cost typically correlates with features, and while managed switches tend to be more expensive, that is not a universal rule. Similarly, both types can have various port counts and speeds, depending on the specific models chosen.