WPA2 uses AES for wireless data encryption at which of the following encryption levels?

WPA2 does not use 64-bit encryption; AES in CCMP mode requires a minimum 128-bit key, making 64-bit an invalid WPA2 encryption level.

CRC (Cyclic Redundancy Check) is an error-detection mechanism used in Ethernet frames, not a message integrity code; WPA2 uses CBC-MAC within CCMP for integrity, not CRC.

WPA2 requires AES operating in CCMP (Counter Mode with Cipher Block Chaining Message Authentication Code Protocol) mode with a 128-bit key, which provides both data confidentiality and cryptographic message integrity. CCMP was specifically designed to replace TKIP after TKIP's RC4-based design was found to have exploitable weaknesses. The 128-bit AES-CCMP pairing is the defining cryptographic requirement that makes WPA2 substantially stronger than its WPA predecessor.

TKIP (Temporal Key Integrity Protocol) was the encryption protocol used by the original WPA standard and is only optionally supported in WPA2 for backward compatibility - it is not the WPA2-mandated protocol.