4 Way HANDSHAKE

Message 1 (M1):

* Authenticator sends EAPOL-Key frame containing an ANonce(Authenticator nonce) to supplicant.

* With this information, supplicant have all necessary input to generate PTK using pseudo-random function(PRF)

Message 2 (M2):

* Supplicant sends an EAPOL-Key frame containing SNonce to the Authenticator.

* Now authenticator has all the inputs to create PTK.

* Supplicant also sent RSN IE capabilities to Authenticator & MIC

* Authenticator derive PTK & validate the MIC as well.

Message 3 (M3):

* If necessary, Authenticator will derive GTK from GMK.

* Authenticator sends EAPOL-Key frame containing ANonce, RSN-IE & a MIC.

* GTK will be delivered (encrypted with PTK) to supplicant.

* Message to supplicant to install temporal keys.

Message 4 (M4):

* Supplicant sends final EAPOL-Key frame to authenticator to confirm temporal keys have been installed.