3Com 4500 Configuration Manual page 138

Table 1-1 Description of port security modes
Security mode
noRestriction
autolearn
secure
Description
In this mode, access to the port is not
restricted.
In this mode, a port can learn a specified
number of MAC addresses and save those
addresses as security MAC addresses. It
permits only packets whose source MAC
addresses are the security MAC addresses
that were learned or configured manually.
When the number of security MAC addresses
reaches the upper limit configured by the
port-security max-count command, the port
changes to work in secure mode and no more
MAC addresses can be added to the port.
In this mode, MAC address learning is
disabled on the port. The port permits packets
whose source MAC addresses are static and
dynamic MAC addresses that were configured
manually.
When the port mode changes from autolearn
to secure, the security MAC addresses that
were learned in the autolearn mode are
permitted to pass through the port.
1-2
Feature
In this mode, neither the
NTK nor the intrusion
protection feature is
triggered.
In either mode, the device
will trigger NTK and
intrusion protection upon
detecting an illegal
packet.