Selects the auto-learning function for the port. Setting this object to inactive(1) disables auto-learning; the user must set securityAddr in order to specify the authorized MAC address. Setting this object to active(2) enables auto-learning of the port's authorized MAC address. The agent first sets the authorized MAC address to 0, then learns the source address of the first error-free frame received by the port. The newly-learned authorized address is reflected in securityAddr, and the status of this object changes to learned(3). The value learned(3) is read-only. Attempts to set this object to learned(3) are rejected with an error-status of badValue(3).