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Which encryption standard should you choose?

You are implementing wireless access at a defense contractor. Specifications say, you must
implement the AES Encryption algorithm. Which encryption standard should you choose?

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A.
WEP

B.
WPA

C.
TKIP

D.
WPA 2

Explanation:

WPA 2 (Wi Fi Protected Access 2) uses AES encryption, which is endorsed by the National Security
Administration.
What is AES?
The Advanced Encryption Standard (AES) is an encryption standard adopted by the U.S. government.
The standard comprises three block ciphers, AES-128, AES-192, and AES-256. Each AES cipher has a
128-bit block size, with key sizes of
128, 192, and 256 bits, respectively. The AES ciphers have been analyzed extensively and are now
used worldwide, as was the case with its predecessor, the Data Encryption Standard (DES).
AES was announced by National Institute of Standards and Technology (NIST) as U.S. FIPS PUB 197
(FIPS 197) on
November 26, 2001 after a 5-year standardization process in which fifteen competing designs were
presented and evaluated before Rijndael was selected as the most suitable. It became effective as a
standard on May 26, 2002. As of
2009, AES is one of the most popular algorithms used in symmetric key cryptography. It is available
in many different encryption packages. AES is the first publicly accessible and open cipher approved
by the NSA for top secret information.

Answer optiond A and B are incorrect. WEP and WPA both use the RC-4 Stream cipher.
What is RC4?
RC4 is a stream cipher designed by Ron Rivest. It is used in many applications, including Transport
Layer Security (TLS), Wired Equivalent Privacy (WEP), Wi-Fi Protected Access (WPA), etc. RC4 is fast
and simple. However, it has weaknesses that argue against its use in new systems. It is especially
vulnerable when the beginning of the output key stream is not discarded, nonrandom or related
keys are used, or a single key stream is used twice. Some ways of using RC4 can lead to very insecure
cryptosystems such as WEP.
Answer option C is incorrect. Temporal Key Integrity Protocol is a substitute for WPA, meant to
replace WEP without requiring that hardware be replaced.
Reference. http.//en.wikipedia.org/wiki/IEEE_802.11i


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