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Which of the following encryption methods use the RC4 technology?

Which of the following encryption methods use the RC4 technology? Each correct answer represents a complete solution. Choose all that apply.

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A.
Dynamic WEP

B.
CCMP

C.
TKIP

D.
Static WEP

Explanation:
Static WEP: Static Wired Equivalent Privacy (WEP) is a layer 2 encryption method that uses the RC4 streaming cipher. The three main intended goals of WEP encryption include confidentiality, access control, and data integrity. Dynamic WEP: Dynamic WEP changes WEP keys dynamically. Dynamic WEP was likely developed as a response to WEP’s security flaws and uses the RC4 cipher.TKIP: TKIP (Temporal Key Integrity Protocol) is an encryption protocol defined in the IEEE 802.11i standard for wireless LANs (WLANs). It is designed to provide more secure encryption than the disreputably weak Wired Equivalent Privacy (WEP). TKIP is the encryption method used in Wi-Fi Protected Access (WPA), which replaced WEP in WLAN products.
TKIP is a suite of algorithms to replace WEP without requiring the replacement of legacy WLAN equipment. TKIP uses the original WEP programming but wraps additional code at the beginning and end to encapsulate and modify it. Like WEP, TKIP uses the RC4 stream encryption algorithm as its basis. Answer option B is incorrect. CCMP (Counter Mode with Cipher Block Chaining Message Authentication Code Protocol) is an IEEE 802.11i encryption protocol created to replace both TKIP, the mandatory protocol in WPA, and WEP, the earlier, insecure protocol. CCMP is a mandatory part of the WPA2 standard, an optional part of the WPA standard, and a required option for Robust Security Network (RSN) Compliant networks. CCMP is also used in the ITU-T home and business networking standard. CCMP, part of the 802.11i standard, uses the Advanced Encryption Standard (AES) algorithm. Unlike in TKIP, key management and message integrity is handled by a single component built around AES using a 128-bit key, a 128-bit block, and 10 rounds of encoding per the FIPS 197
standard.
What is AES?
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, adopted from a larger collection originally published as Rijndael. AES is based on a design principle known as a Substitution permutation network. It is fast in both software and hardware. It is relatively easy to implement, and requires little memory. Unlike its predecessor DES, AES does not use a Feistel network. AES has a fixed block size of 128 bits and a key size of 128, 192, or 256 bits, whereas Rijndael can be specified with block and key sizes in any multiple of 32 bits, with a minimum of 128 bits and a maximum of 256 bits. Assuming one byte equals 8 bits, the fixed block size of 128 bits is 128 8 = 16 bytes. AES operates on a 4 4 array of bytes, termed the state. Most AES calculations are done in a special finite field.
The AES cipher is specified as a number of repetitions of transformation rounds that convert the input plain-text into the final output of cipher-text. Each round consists of several processing steps, including one that depends on the encryption key. A set of reverse rounds are applied to transform cipher-text back into the original plain-text using the same encryption key.
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 keystream is not discarded, nonrandom or related keys are used, or a single keystream is used twice. Some ways of using RC4 can lead to very insecure cryptosystems such as WEP.

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