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Which of the following algorithms is an iterated block cipher that works by repeating the defined steps multiple times and has a 128-bit block size, having key sizes of 128, 192, and 256 bits?
Suggested Answer: D
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AES (Advanced Encryption Standard) is an iterated block cipher that works by repeating the defined steps multiple times and has a 128-bit block size, having key sizes of 128, 192, and 256 bits. AES is a symmetric-key algorithm that encrypts and decrypts data using the same secret key. AES operates on a 4x4 matrix of bytes called the state, which undergoes 10, 12, or 14 rounds of transformation depending on the key size. Each round consists of four steps: sub-bytes, shift-rows, mix-columns, and add-round-key. AES is widely used for securing data in various applications and platforms, such as web browsers, VPNs, wireless networks, and smart grids. AES is the algorithm that matches the description given in the question. Reference:
AES - Week 4: Cryptography Techniques
Advanced Encryption Standard (AES) - NIST
AES Encryption and Decryption Online Tool - Code Beautify
43 comments · newest first
KE
Kenda
11 months ago
AES is solid, but I still have my doubts about its security in the long run.
LI
Lillian
11 months ago
I thought MD5 was a hashing algorithm, not a cipher?
CA
Carma
11 months ago
Wait, isn't DSA a digital signature algorithm?
BE
Berry
12 months ago
Agreed, AES has those key sizes and block size!
MA
Marlon
12 months ago
Definitely AES, it's the standard for block ciphers!
JU
Justine
1 year ago
I keep mixing up MD5 and SHA, but I don't think either of them are block ciphers like AES.
LA
Laurene
1 year ago
I practiced a similar question, and I believe AES is the only one that fits the description given the block size and key lengths.
EM
Emilio
1 year ago
I'm not entirely sure, but I feel like DSA is more about digital signatures, not block ciphers.
GE
Georgiana
1 year ago
I think the answer is AES because I remember it being an iterated block cipher with those key sizes.
AN
Annamaria
1 year ago
AES seems like the most likely answer based on the details provided. I'll mark that down unless I can think of a reason why another option might fit better. Gotta move quickly on these exam questions!
LA
Laila
1 year ago
I'm not totally sure about this one. I know AES is a common block cipher, but I'm not positive it's the only one that matches all the criteria here. I'll have to think it through carefully.
TR
Tracey
1 year ago
Okay, I've got this. The algorithm with a 128-bit block size and variable key sizes of 128, 192, and 256 bits is AES. I'm confident that's the right answer.
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Ronna
1 year ago
This one looks tricky, but I think I can figure it out. Let me think through the key details - it's an iterated block cipher with a 128-bit block size and variable key sizes. That narrows it down a bit.
TI
Tijuana
1 year ago
Hmm, I'm a little confused on the difference between some of these algorithms. I'll need to review my notes on block ciphers and their properties to make sure I understand which one fits the description.
JE
Jesus
2 years ago
I'll go with AES. It's the industry standard for a reason, right? Can't imagine the exam makers would try to trick us on this one.
NO
Nobuko
2 years ago
AES is the best option here. It's a reliable choice for encryption.
VE
Vernice
2 years ago
I think AES is the correct choice too. It's a strong algorithm.
NA
Nathan
2 years ago
I agree, AES is known for its security and efficiency.
LO
Long
2 years ago
AES is definitely the way to go. It's widely used and trusted.
LO
Lorrine
2 years ago
D. AES. Hands down. The others just don't match up to the spec. Unless, of course, this is some kind of trick question...?
BE
Beatriz
2 years ago
Hah, easy peasy. D, AES. Anything else would just be silly. Though I hear MD5 is great for securing my passwords...
CR
Cristen
2 years ago
I'm gonna have to go with D. AES is the only one that fits the description given in the question.
KA
Katina
2 years ago
AES, of course! The key sizes and block size are a dead giveaway. Can't go wrong with good old AES.
FR
Frank
2 years ago
AES is known for its strong security features with key sizes and block size like that.
KA
Katlyn
2 years ago
AES is definitely the way to go for secure encryption.
JU
Julene
2 years ago
I agree, AES is a solid choice with those key sizes and block size.
SH
Sherman
2 years ago
AES, for sure. It's the algorithm that keeps my grandma's cookie recipes safe from prying eyes.
LA
Layla
2 years ago
Easy, it's D. AES. I can never remember all those other cryptographic acronyms, but AES is the one I know.
VA
Vannessa
2 years ago
Hmm, I think it's D. AES, the Advanced Encryption Standard. It's the go-to algorithm these days.
GA
Gail
2 years ago
Definitely, AES is the way to go for encryption.
TR
Trevor
2 years ago
Yeah, AES is widely used for its security and efficiency.
SH
Shannan
2 years ago
I think it's D. AES, the Advanced Encryption Standard.
ZA
Zachary
2 years ago
I'm not sure, but AES does seem like the most likely choice.
TO
Tora
2 years ago
Definitely AES. I've used it in my projects and it's rock solid.
KI
King
2 years ago
AES with its 128-bit block size is very reliable.
SH
Shawn
2 years ago
I've heard AES is the best option for encryption.
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Sue
2 years ago
I agree, AES is very secure.
DO
Dottie
2 years ago
AES is definitely the right choice.
ME
Mel
2 years ago
I've heard great things about AES, it's a popular choice for encryption.
LY
Lynsey
2 years ago
AES is definitely the way to go for encryption.
AN
Angelyn
2 years ago
I agree, AES is very reliable and secure.
CL
Clorinda
2 years ago
I agree with Denna, AES fits the description.
DE
Denna
2 years ago
I think the answer is D) AES.