Private VLANs (PVLANs) are used to segment devices on the same subnet and switch so they cannot communicate with each other, while still accessing a shared resource like a router or gateway. This is often used in shared hosting or DMZ environments.
A: ACLs (Access Control Lists) control traffic between networks, not within the same VLAN.
B: Trunking carries multiple VLANs between switches but does not isolate devices.
C: Port security limits MAC addresses per port but doesn't isolate communication between ports.
# Reference:
CompTIA Network+ N10-009 Official Objectives: 3.4 - Compare and contrast access control methods.