What is MAC Limit Port Security?

MAC Limit Port Security is a feature that restricts the number of MAC addresses allowed on a specific switch port. It helps prevent unauthorized devices from connecting to the network. When the limit is exceeded, the port can be shut down or placed in a protective state. This feature enhances network security by controlling access to the network and ensures that only authorized devices can communicate through specific ports, reducing security risks.

MAC Limit Port Security works by caching the MAC addresses of devices connected to a specific port in a MAC Address Table for reference. The system tracks the number of MAC addresses learned on the port. Once the configured limit is reached, further connections are restricted.

While only the allowed MAC addresses can be permitted on the network, this doesn’t usually involve a “lease time” like DHCP. Once a MAC address is learned and stored, it’s referenced until the port security configuration is modified or the device disconnects. If the limit is exceeded or an unauthorized device attempts to connect, the port can either be shut down, placed in an error-disabled state, or restricted depending on the configuration.

Content created by Mike Day