First of all, @Arne Bier your negative comment does not motivate me at all instead I'm ignoring your negativity and pasting below Cisco's own statement:"
IEEE 802.1X Authentication Initiation and Message Exchange
During IEEE 802.1X authentication, the router or the supplicant can initiate authentication. If you enable authentication on a port by using the authentication port-control auto interface configuration command, the router initiates authentication when the link state changes from down to up or periodically if the port remains up and unauthenticated.
and for the second command dot1x pae authenticator
Kieth has answered this in his reply here: https://learningnetwork.cisco.com/thread/14910
Keith's reply: " If we use the command "no dot1x pae authenticator" on the port, the switch will still have dot1x enabled on the port, but will not allow clients to authenticate and will leave the state as unauthorized. "
|Step 9||dot1x pae [supplicant | authenticator | both]|
Device(config-if)# dot1x pae authenticator
Sets the Port Access Entity (PAE) type.
supplicant—The interface acts only as a supplicant and does not respond to messages that are meant for an authenticator.
authenticator-—The interface acts only as an authenticator and does not respond to any messages meant for a supplicant.
both—The interface behaves both as a supplicant and as an authenticator and thus does respond to all dot1x messages.
Hence the above highlighted blue comment justifies what Keith said indirectly.
Sooo ... @Arne Bier ... if you have some info that is not in the Cisco Press Books or Cisco Documents etc etc.. then do share.
... that was the homework I did.. what is yours ????