Which of the following key types are defined in the 802.11i Authentication and Key Management (AKM)?
Each correct answer represents a complete solution. Choose all that apply.

A.
Pairwise Master Key (PMK)

B.
Group Master Key (GMK)

C.
Pairwise Transient Key (PTK)

D.
Group Temporal Key (GTK)

Explanation:
The key types that are defined in the 802.11i Authentication and Key Management (AKM) are as follows. Pairwise Master Key (PMK). Pairwise Master Key (PMK) is the highest order key used within the 802.11i amendment. It is derived directly from a preshared key and can also be derived from the Extensible Authentication Protocol (EAP). It is a cryptography key that is used to derive lower level keys. Group Temporal Key (GTK). 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). Pairwise Transient Key (PTK). 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. 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).
Group Master Key (GMK). Group Master Key is an auxiliary key. It may be used to derive a group temporal key (GTK).