Which technology expands network segmentation capabilities?

Virtual LANs (VLANs) enhance network segmentation capabilities by allowing network administrators to create distinct broadcast domains within a single physical network. This enables the logical separation of networks, improving security, reducing congestion, and more effectively managing traffic. Each VLAN can represent different departments, projects, or types of traffic, which facilitates better organization and control over network resources.

By using VLANs, traffic that belongs to one segment does not interfere with traffic from another, even though they share the same physical infrastructure. This isolation helps in enhancing both security and performance, as network policies and access controls can be applied specifically to each VLAN. As a result, VLANs are fundamental for large organizations that require a scalable and efficient network management strategy.

In contrast, the other options, while beneficial in their own right, do not specifically focus on expanding segmentation capabilities in the same way as VLANs. For instance, link aggregation combines multiple network connections to increase bandwidth, port mirroring replicates traffic for monitoring purposes, and trunking deals with carrying multiple VLAN traffic across a single link but does not create or define the segmentation itself.