Port Security
A switch feature that limits which MAC addresses can use a port to block unauthorized devices.
Port security is a managed-switch (Layer 2) feature that restricts which MAC addresses may communicate through a physical port. An administrator sets a maximum MAC count per port and chooses how addresses are learned: dynamically, statically, or sticky (learned then saved to the config). On a violation — an unauthorized MAC or exceeding the limit — the switch responds in protect (silently drop), restrict (drop and log), or shutdown (disable the port, needing manual recovery) mode. Unlike 802.1X, which authenticates identity via a server, port security filters by MAC, which can be spoofed.
PlayPrepHQ study notes are written and reviewed against primary exam sources. How we create & review content →