GTK (Group Temporal Key) KDE Contains the group key for multicast/broadcast traffic
Group Temporal Key (typically 16 or 32 bytes depending on cipher)
Key ID (bits 0-1 of keyinfo byte) - identifies which GTK slot
Tx flag (bit 2 of keyinfo byte) - this key is used for Tx by AP
GTK (Group Temporal Key) KDE Contains the group key for multicast/broadcast traffic