Eccouncil 212-81 Exam - Topic 2 Question 22 Discussion

Actual exam question for Eccouncil's 212-81 exam

Question #: 22
Topic #: 2

Symmetric algorithm. Designed by James Massey and Xuejia Lai. Operates on 64 bit blocks and has a 128 bit key. Consists of 8 identical transformations each round and an output transformation.

AIDEA

BRSA

CCAST

DDES

Show Suggested Answer

Suggested Answer: A

CBC-MAC

https://en.wikipedia.org/wiki/CBC-MAC

A cipher block chaining message authentication code (CBC-MAC) is a technique for constructing a message authentication code from a block cipher. The message is encrypted with some block cipher algorithm in CBC mode to create a chain of blocks such that each block depends on the proper encryption of the previous block. This interdependence ensures that a change to any of the plaintext bits will cause the final encrypted block to change in a way that cannot be predicted or counteracted without knowing the key to the block cipher. Using in WPA2 for integrity check and provides security against a replay attack.

by Glory at Jul 25, 2023, 09:14 AM

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Leanna

8 months ago

I’m not sure, but I thought CAST was more common.

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Lynsey

8 months ago

Nope, it's not RSA. Totally different type of algorithm.

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King

8 months ago

Wait, 128-bit key? I didn't know that about IDEA!

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Mary

8 months ago

I thought it was DES, but IDEA makes sense too.

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Colette

9 months ago

That's definitely IDEA, right?

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Pamella

9 months ago

RSA is definitely not a symmetric algorithm, so I think we can rule that one out right away.

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Tiffiny

9 months ago

CAST has a 128-bit key too, but I don't recall if it has 8 identical transformations like the question states.

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Elina

9 months ago

I remember studying DES, but it uses a 56-bit key, so it can't be the answer here.

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Daren

9 months ago

I think this sounds like IDEA, but I'm not entirely sure about the block size.

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Irma

9 months ago

Configuring the failover link with stateful properties sounds important for maintaining connection updates. I'll make sure to include that in my approach.

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Felix

10 months ago

I'm a bit confused by this question. The XSLT style sheet doesn't seem to be doing much, so I'm not sure how to predict the output. I'll need to think this through step-by-step.

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Marsha

10 months ago

I'm a bit uncertain, but I feel like it might be more like a method since it executes specific tasks when called upon.

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Dianne

1 year ago

Hold on, did they say 'Symmetric algorithm'? I thought we were learning about asymmetric encryption. This exam is really messing with my head.

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Yuriko

1 year ago

D) DES

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Delsie

1 year ago

Yeah, symmetric encryption is a whole different ball game compared to asymmetric encryption.

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Lino

1 year ago

A) IDEA

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Eden

1 year ago

I know, it can get confusing with all the different encryption algorithms.

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Trevor

1 year ago

D) DES

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Renato

1 year ago

C) CAST

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Gearldine

1 year ago

B) RSA

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Janna

1 year ago

A) IDEA

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Lashaun

1 year ago

Wait, isn't IDEA the algorithm used to encrypt your data before sending it to the government? Kidding, kidding, I'm sure it's just a coincidence.

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Clare

1 year ago

C) CAST

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Reita

1 year ago

D) DES

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Tony

1 year ago

A) IDEA

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Joni

1 year ago

I was gonna say IDEA, but then I remembered that IDEA stands for 'International Data Encryption Algorithm', so it has to be IDEA. Nailed it!

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Abel

1 year ago

DES has a 64-bit block size, so that can't be it. My money's on IDEA, sounds like a perfect match.

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Galen

1 year ago

Hmm, IDEA does fit the details, but CAST could also be a possibility. I'm not sure, this one's tricky.

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Chaya

1 year ago

Let's go with IDEA, it matches the description better.

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Shantell

1 year ago

But CAST could also work, it's a tough choice.

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Leonida

1 year ago

I agree, IDEA seems like the best fit.

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Brendan

1 year ago

I think it might be IDEA.

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Rodolfo

1 year ago

Let's go with IDEA, it matches the description better.

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Timothy

1 year ago

But CAST could also work, it's a tough choice.

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Dacia

1 year ago

I agree, IDEA seems like the best fit.

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Arlene

1 year ago

I think it might be IDEA.

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Stephane

1 year ago

I'm not sure, but I think it could be A) IDEA.

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Sarah

1 year ago

I agree with Keneth, DES fits the description given.

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Hubert

1 year ago

I think it's IDEA, that algorithm sounds exactly like the description.

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Vicki

1 year ago

Yes, IDEA is the correct answer for that algorithm.

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Raul

1 year ago

I agree, IDEA fits the description perfectly.

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Keneth

1 year ago

I think the answer is D) DES.

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Heike

1 year ago

I'm not sure, but I think it could also be A) IDEA.

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Lashandra

1 year ago

I agree with Stevie, DES fits the description given.

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Stevie

1 year ago

I think the answer is D) DES.

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