Cisco Exam Questions

Which two are characteristics of WPA?

Which two are characteristics of WPA? (Choose two.)

A.
implements a key mixing function before passing the initialization vector to the RC4
algorithm

B.
uses a 40-bit key with 24-bit initialization vector

C.
introduces a 64-bit MIC mechanism

D.
WPA does not allow Pre-Shared key mode

E.
makes the use of AES mandatory

Explanation:
On October 31, 2002, the Wi-Fi Alliance endorsed TKIP under the name Wi-Fi Protected
Access (WPA).
TKIP and the related WPA standard implement three new security features to address
security problems encountered in WEP protected networks. First, TKIP implements a key
mixing function that combines the secret root key with the initialization vector before
passing it to the RC4 initialization. WEP, in comparison, merely concatenated the
initialization vector to the root key, and passed this value to the RC4 routine. This
permitted the vast majority of the RC4 based WEP related key attacks. Second, WPA
implements a sequence counter to protect against replay attacks. Packets received out
of order will be rejected by the access point. Finally, TKIP implements a 64-bit Message
Integrity Check (MIC).
https://en.wikipedia.org/wiki/Temporal_Key_Integrity_Protocol