EC-COUNCIL 212-81 Online Practice Questions and Exam Preparation

EC-COUNCIL 212-81 Online Questions & Answers

• Question 191:

  Message hidden in unrelated text. Sender and receiver have pre-arranged to use a pattern to remove certain letters from the message which leaves only the true message behind.

  A. Caesar Cipher
  B. Null Ciphers
  C. Vigenere Cipher
  D. Playfair Cipher
  B. Null Ciphers

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  Explanation

  Null Ciphers https://en.wikipedia.org/wiki/Null_cipher A null cipher, also known as concealment cipher, is an ancient form of encryption where the plaintext is mixed with a large amount of non-cipher material. Today it is regarded as a simple form of steganography, which can be used to hide ciphertext.

• Question 192:

  Storing private keys with a third party is referred to as what?

  A. Key caching
  B. Key storage
  C. Key banking
  D. Key escrow
  D. Key escrow

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  Explanation

  Key escrow https://en.wikipedia.org/wiki/Key_escrow Key escrow (also known as a "fair" cryptosystem) is an arrangement in which the keys needed to decrypt encrypted data are held in escrow so that, under certain circumstances, an authorized third party may gain access to those keys. These third parties may include businesses, who may want access to employees' secure business-related communications, or governments, who may wish to be able to view the contents of encrypted communications (also known as exceptional access).

• Question 193:

  This hash function uses 512-bit blocks and implements preset constants that change after each repetition. Each block is hashed into a 256-bit block through four branches that divides each 512 block into sixteen 32-bit words that are further encrypted and rearranged.

  A. SHA-256
  B. FORK-256
  C. SHA-1
  D. RSA
  B. FORK-256

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  Explanation

  FORK-256 https://en.wikipedia.org/wiki/FORK-256 FORK-256 was introduced at the 2005 NIST Hash workshop and published the following year.[6] FORK-256 uses 512-bit blocks and implements preset constants that change after each repetition. Each block is hashed into a 256-bit block through four branches that divides each 512 block into sixteen 32-bit words that are further encrypted and rearranged.

• Question 194:

  Which one of the following wireless standards uses the Advanced Encryption Standard (AES) using the Counter Mode-Cipher Block Chaining (CBC)-Message Authentication Code (MAC) Protocol (CCMP)?

  A. WEP
  B. WEP2
  C. WPA
  D. WPA2
  D. WPA2

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  Explanation

  WPA2

  https://en.wikipedia.org/wiki/Wi-Fi_Protected_Access#WPA2 WPA2 use the Counter Mode-Cipher Block Chaining (CBC)-Message Authentication Code (MAC) Protocol (CCMP).

• Question 195:

  Original, unencrypted information is referred to as ____.

  A. text
  B. plaintext
  C. ciphertext
  D. cleartext
  B. plaintext

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  Explanation

  plaintext https://en.wikipedia.org/wiki/Plaintext In cryptography, plaintext usually means unencrypted information pending input into cryptographic algorithms, usually encryption algorithms. Cleartext usually refers to data that is transmitted or stored unencrypted ("in clear").

• Question 196:

  Bruce Schneier is a well-known and highly respected cryptographer. He has developed several pseudo random number generators as well as worked on teams developing symmetric ciphers. Which one of the following is a symmetric block cipher designed in 1993 by Bruce Schneier team that is unpatented?

  A. Pegasus
  B. Blowfish
  C. SHA1
  D. AES
  B. Blowfish

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  Explanation

  Blowfish

  https://en.wikipedia.org/wiki/Blowfish_(cipher)

  Blowfish is a symmetric-key block cipher, designed in 1993 by Bruce Schneier and included in many cipher suites and encryption products.

• Question 197:

  Hash. Created by Ronald Rivest. Replaced MD4. 128 bit output size, 512 bit block size, 32 bit word size, 64 rounds. Infamously compromised by Flame malware in 2012. A. Keccak

  B. MD5

  C. SHA-1

  D. TIGER

  Correct Answer. B
  B

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  Explanation

  MD5 https://en.wikipedia.org/wiki/MD5 The MD5 message-digest algorithm is a widely used hash function producing a 128-bit hash value. Although MD5 was initially designed to be used as a cryptographic hash function, it has been found to suffer from extensive vulnerabilities. It can still be used as a checksum to verify data integrity, but only against unintentional corruption. It remains suitable for other non-cryptographic purposes, for example for determining the partition for a particular key in a partitioned database. MD5 was designed by Ronald Rivest in 1991 to replace an earlier hash function MD4, and was specified in 1992 as RFC 1321

• Question 198:

  The art and science of writing hidden messages so that no one suspects the existence of the message, a type of security through obscurity. Message can be hidden in picture or audio file for example. Uses least significant bits in a file to store data.

  A. Steganography
  B. Cryptosystem
  C. Avalanche effect
  D. Key Schedule
  A. Steganography

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  Explanation

  Steganography

  https://en.wikipedia.org/wiki/Steganography

  Steganography is the practice of concealing a file, message, image, or video within another file, message, image, or video.

  The first recorded use of the term was in 1499 by Johannes Trithemius in his Steganographia, a treatise on cryptography and steganography, disguised as a book on magic. Generally, the hidden messages appear to be (or to be part of)

  something else:

  images, articles, shopping lists, or some other cover text. For example, the hidden message may be in invisible ink between the visible lines of a private letter. Some implementations of steganography that lack a shared secret are forms of

  security through obscurity, and key-dependent steganographic schemes adhere to Kerckhoffs's principle.

• Question 199:

  What size key does Skipjack use?

  A. 128 bit
  B. 56 bit
  C. 80 bit
  D. 256 bit
  C. 80 bit

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  Explanation

• Question 200:

  Developed by Netscape and has been replaced by TLS. It was the preferred method used with secure websites.

  A. OCSP
  B. VPN
  C. CRL
  D. SSL
  D. SSL

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  Explanation

  SSL https://en.wikipedia.org/wiki/Transport_Layer_Security Transport Layer Security (TLS), and its now-deprecated predecessor, Secure Sockets Layer (SSL), are cryptographic protocols designed to provide communications security over a computer network. Several versions of the protocols find widespread use in applications such as web browsing, email, instant messaging, and voice over IP (VoIP). Websites can use TLS to secure all communications between their servers and web browsers. Netscape developed the original SSL protocols, and Taher Elgamal, chief scientist at Netscape Communications from 1995 to 1998, has been described as the "father of SSL". SSL version 1.0 was never publicly released because of serious security flaws in the protocol. Version 2.0, released in February 1995, contained a number of security flaws which necessitated the design of version 3.0. Released in 1996, SSL version 3.0 represented a complete redesign of the protocol produced by Paul Kocher working with Netscape engineers Phil Karlton and Alan Freier, with a reference implementation by Christopher Allen and Tim Dierks of Consensus Development.