212-81 exam material before purchase; this will help you to figure out what the actual product will offer you and whether these features will help a prospective user to learn within a week. Also, upon purchase, the candidate will be entitled to 1 year free updates, which will help candidates to stay up-to-date with 212-81 news feeds and don’t leave any chance which can cause their failure. The 100% refund policy is offered to all esteemed users, in the case for any reason, any candidates fail in 212-81 certification exam so he may claim the refund.
EC-COUNCIL 212-81 Exam Syllabus Topics:
| Topic | Details |
|---|---|
| Topic 1 |
|
| Topic 2 |
|
| Topic 3 |
|
| Topic 4 |
|
| Topic 5 |
|
| Topic 6 |
|
| Topic 7 |
|
| Topic 8 |
|
| Topic 9 |
|
| Topic 10 |
|
| Topic 11 |
|
>> 212-81 Reliable Exam Tutorial <<
Hot 212-81 Reliable Exam Tutorial | Valid New 212-81 Exam Objectives: Certified Encryption Specialist 100% Pass
With over a decade’s business experience, our 212-81 test torrent attached great importance to customers’ purchasing rights all along. There is no need to worry about virus on buying electronic products. For we make endless efforts to assess and evaluate our 212-81 exam prep’ reliability for a long time and put forward a guaranteed purchasing scheme, we have created an absolutely safe environment and our 212-81 Exam Question are free of virus attack. If there is any doubt about it, professional personnel will handle this at first time, and you can also have their remotely online guidance to install and use our 212-81 test torrent.
EC-COUNCIL Certified Encryption Specialist Sample Questions (Q171-Q176):
NEW QUESTION # 171
An attack that is particularly successful against block ciphers based on substitution-permutation networks. For a block size b, holds b-k bits constant and runs the other k through all 2k possibilities. For k=1, this is just deferential cryptanalysis, but with k>1 it is a new technique.
- A. Chosen Plaintext Attack
- B. Linear Cryptanalysis
- C. Differential Cryptanalysis
- D. Integral Cryptanalysis
Answer: D
Explanation:
Integral Cryptanalysis
https://en.wikipedia.org/wiki/Integral_cryptanalysis
Integral cryptanalysis is a cryptanalytic attack that is particularly applicable to block ciphers based on substitution-permutation networks. It was originally designed by Lars Knudsen as a dedicated attack against Square, so it is commonly known as the Square attack. It was also extended to a few other ciphers related to Square: CRYPTON, Rijndael, and SHARK. Stefan Lucks generalized the attack to what he called a saturation attack and used it to attack Twofish, which is not at all similar to Square, having a radically different Feistel network structure. Forms of integral cryptanalysis have since been applied to a variety of ciphers, including Hierocrypt, IDEA, Camellia, Skipjack, MISTY1, MISTY2, SAFER++, KHAZAD, and FOX (now called IDEA NXT).
Incorrect answers:
Chosen Plaintext Attack - is an attack model for cryptanalysis which presumes that the attacker can obtain the ciphertexts for arbitrary plaintexts. The goal of the attack is to gain information that reduces the security of the encryption scheme.
Linear Cryptanalysis - is a general form of cryptanalysis based on finding affine approximations to the action of a cipher. Attacks have been developed for block ciphers and stream ciphers. Linear cryptanalysis is one of the two most widely used attacks on block ciphers.
Differential Cryptanalysis - is a general form of cryptanalysis applicable primarily to block ciphers, but also to stream ciphers and cryptographic hash functions. In the broadest sense, it is the study of how differences in information input can affect the resultant difference at the output. In the case of a block cipher, it refers to a set of techniques for tracing differences through the network of transformation, discovering where the cipher exhibits non-random behavior, and exploiting such properties to recover the secret key (cryptography key).
NEW QUESTION # 172
In a ______ the attacker discovers a functionally equivalent algorithm for encryption and decryption, but without learning the key.
- A. Global deduction
- B. Instance deduction
- C. Total break
- D. Information deduction
Answer: A
Explanation:
Global deduction
https://en.wikipedia.org/wiki/Cryptanalysis
Global deduction - the attacker discovers a functionally equivalent algorithm for encryption and decryption, but without learning the key.
Incorrect answers:
Instance (local) deduction - the attacker discovers additional plaintexts (or ciphertexts) not previously known.
Information deduction - the attacker gains some Shannon information about plaintexts (or ciphertexts) not previously known.
Total break - the attacker deduces the secret key.
NEW QUESTION # 173
Which of the following is a fundamental principle of cryptography that holds that the algorithm can be publicly disclosed without damaging security?
- A. Babbage's principle
- B. Kerkchoff's principle
- C. Shamir's principle
- D. Vigenere's principle
Answer: B
Explanation:
Kerkchoff's principle
https://en.wikipedia.org/wiki/Kerckhoffs%27s_principle
Kerckhoffs's principle (also called Kerckhoffs's desideratum, assumption, axiom, doctrine or law) of cryptography was stated by Netherlands born cryptographer Auguste Kerckhoffs in the 19th century: A cryptosystem should be secure even if everything about the system, except the key, is public knowledge.
Kerckhoffs's principle was reformulated (or possibly independently formulated) by American mathematician Claude Shannon as "the enemy knows the system", i.e., "one ought to design systems under the assumption that the enemy will immediately gain full familiarity with them". In that form, it is called Shannon's maxim. This concept is widely embraced by cryptographers, in contrast to "security through obscurity", which is not.
NEW QUESTION # 174
With Cipher-block chaining (CBC) what happens?
- A. The block cipher is turned into a stream cipher
- B. The cipher text from the current round is XORed with the plaintext for the next round
- C. Each block of plaintext is XORed with the previous ciphertext block before being encrypted
- D. The message is divided into blocks and each block is encrypted separately. This is the most basic mode for symmetric encryption
Answer: C
Explanation:
Each block of plaintext is XORed with the previous ciphertext block before being encrypted
https://en.wikipedia.org/wiki/Block_cipher_mode_of_operation#Cipher_block_chaining_(CBC) In CBC mode, each block of plaintext is XORed with the previous ciphertext block before being encrypted. This way, each ciphertext block depends on all plaintext blocks processed up to that point. To make each message unique, an initialization vector must be used in the first block.
NEW QUESTION # 175
In a Feistel cipher, the two halves of the block are swapped in each round. What does this provide?
- A. Avalanche
- B. Confusion
- C. Diffusion
- D. Substitution
Answer: B
Explanation:
Confusion
https://en.wikipedia.org/wiki/Confusion_and_diffusion#Definition
Confusion means that each binary digit (bit) of the ciphertext should depend on several parts of the key, obscuring the connections between the two.
The property of confusion hides the relationship between the ciphertext and the key.
This property makes it difficult to find the key from the ciphertext and if a single bit in a key is changed, the calculation of the values of most or all of the bits in the ciphertext will be affected.
Confusion increases the ambiguity of ciphertext and it is used by both block and stream ciphers.
Incorrect answer:
Avalanche - The avalanche effect is the desirable property of cryptographic algorithms, typically block ciphers and cryptographic hash functions, wherein if an input is changed slightly (for example, flipping a single bit), the output changes significantly (e.g., half the output bits flip). In the case of high-quality block ciphers, such a small change in either the key or the plaintext should cause a drastic change in the ciphertext. The actual term was first used by Horst Feistel, although the concept dates back to at least Shannon's diffusion.
Diffusion - Diffusion means that if we change a single bit of the plaintext, then (statistically) half of the bits in the ciphertext should change, and similarly, if we change one bit of the ciphertext, then approximately one half of the plaintext bits should change.[2] Since a bit can have only two states, when they are all re-evaluated and changed from one seemingly random position to another, half of the bits will have changed state.
Substitution - Substitution technique is a classical encryption technique where the characters present in the original message are replaced by the other characters or numbers or by symbols.
NEW QUESTION # 176
......
The purchase process of our 212-81 question torrent is very convenient for all people. In order to meet the needs of all customers, our company is willing to provide all customers with the convenient purchase way. The PDF version of our 212-81 study tool is very practical, which is mainly reflected on the special function. As I mentioned above, our company are willing to provide all people with the demo for free. You must want to know how to get the trial demo of our 212-81 question torrent; the answer is the PDF version. You can download the free demo form the PDF version of our 212-81 exam torrent. Maybe you think it does not prove the practicality of the PDF version, do not worry, we are going to tell us another special function about the PDF version of our 212-81 study tool.
New 212-81 Exam Objectives: https://www.pdf4test.com/212-81-dump-torrent.html
