Which of the following keys is derived by Pairwise Master Key (PMK)?
A.
Private Key
B.
Pairwise Transient Key
C.
Public Key
D.
Group Temporal Key
Explanation:
Pairwise Transient Key is derived from the pairwise master key (PMK), Authenticator address (AA), Supplicant address (SPA), Authenticator nonce (A Nonce), and Supplicant nonce (S Nonce) using pseudorandom function (PRF). Pairwise Transient Key (PTK) is a 64-byte key that comprises the following. 16 bytes of EAPOL-Key Confirmation Key (KCK). This key is used to compute MIC on WPA EAPOL Key message. 16 bytes of EAPOL-Key Encryption Key (KEK). AP uses this key to encrypt additional data sent (in the ‘Key Data’ field) to the client. 16 bytes of Temporal Key (TK). This key is used to encrypt/decrypt unicast data packets. 8 bytes of Michael MIC Authenticator Tx Key. This key is used to compute MIC on unicast data packets transmitted by the AP. 8 bytes of Michael MIC Authenticator Rx Key. This key is used to compute MIC on unicast data packets transmitted by the station.Answer D is incorrect. Group Temporal Key (GTK) is a random value that is assigned by the broadcast/multicast source. It is used to protect broadcast/multicast medium access control (MAC) protocol data units. It is derived from a group master key (GMK).
Answer A and C are incorrect. Private and public keys are not derived by Pairwise Master Key (PMK).
These keys are used in cryptography techniques.