Port security features

The need to know (NTK) feature prevents traffic interception by checking the destination MAC address in the outbound frames. The feature ensures that frames are sent only to the following hosts:

• Hosts that have passed authentication.

• Hosts whose MAC addresses have been learned or configured on the access device.

The intrusion protection feature checks the source MAC address in inbound frames for illegal frames, and takes a predefined action on each detected illegal frame. The action can be disabling the port temporarily, disabling the port permanently, or blocking frames from the illegal MAC address for 3 minutes (not user configurable).

A frame is illegal if its source MAC address cannot be learned in a port security mode or it is from a client that has failed 802.1X or MAC authentication.