What statements are true about 802.

A. 802.11w (now part of 802.11-2012) introduces protection for management frames, especially disassociation and deauthentication frames, helping prevent spoofing-based DoS attacks. However, it cannot prevent all types of Layer 2 DoS (e.g., RF jamming).

D. Specifically, 802.11w protects disassociation and deauthentication frames by signing them with cryptographic keys.

Incorrect:

B. The MAC header and PHY preamble are not encrypted under any standard.

C. Authentication and association frames are not protected by 802.11w; only certain management frames are.