Deck 6: Encryption

Question 1

Which is a block cipher developed by Belgian researchers and providing 128-,192-,and 256-bit key sizes?

A)AES
B)Blowfish
C)DES3
D)RSA

Answer 1

A

Question 2

Which is true about public key encryption?

A)It uses symmetric keys.
B)It uses two different keys.
C)Both keys must be closely protected to avoid hacking.
D)It is based on the PGP protocol.

Answer 2

B

Question 3

Which is NOT an encryption method?

A)AES
B)ASCII
C)DES
D)PGP

Answer 3

B

Question 4

Changing a message in a such a way that it can be read easily by the intended recipient but cannot be read easily by any intercepting party is called ____________.

Question 5

Many encryption techniques such as XOR are easily broken because:

A)brute force techniques can break them
B)their basis in binary numbers makes them easy targets for math processors
C)their public keys are readily available
D)the underlying letter and word frequency can still be determined

Question 6

Operations not found in normal math that can be performed on binary numbers include all of the following EXCEPT:

A)AND
B)OR
C)NOT
D)XOR

Question 7

Which is a very complicated block cipher using 128-bit keys to generate sub-keys to be applied to multiple blocks at the same time?

A)AES
B)DES
C)DES3
D)IDEA

Question 8

Which is a symmetric block cipher developed in 1993 that provides variable-length key sizes ranging from 32 to 448 bits?

A)AES
B)Blowfish
C)DES3
D)IDEA

Question 9

Which is NOT a way in which quantum physics might improve encryption in the future?

A)Computers based on quantum physics would be much faster.
B)If someone tried to read a key without authorization,it could result in destruction of the key.
C)Transferring keys would be immune to interference with subatomic particles.
D)Transferring keys could be based on changing states of subatomic particles.

Question 10

Which is a powerful password cracker that works on Windows and Linux platforms?

A)Brutus
B)John the Ripper
C)Quantum Cracker
D)Solarwinds

Question 11

Which is a symmetric key encryption system?

A)AES
B)DES
C)PGP
D)RSA

Question 12

Which is a very early encryption method?

A)AES
B)Caesar cipher
C)DES3
D)WEP

Question 13

Attempting to determine a password by simply trying every possible combination within the set parameters until successful is called:

A)authentication auditing
B)brute force
C)password cracking
D)password recovery

Question 14

An improvement over the Caesar cipher is based on ____________ substitution.

Question 15

Which type of encrypted communication is most common?

A)Computer and Internet communications
B)Radio communications
C)Telephone conversations
D)Written documents

Question 16

Which is a weakness of Data Encryption Standard?

A)It is based on a 1970s era block cipher.
B)It's complexity in scrambling text makes it very processor-intensive and slow.
C)The key must be transmitted,thus risking it being compromised.
D)Throughput is minimal,making it a poor choice for large files.

Question 17

Which is a public key encryption standard developed by three mathematicians in 1977 that provides very high but slow security?

A)AES
B)DES
C)DES3
D)RSA

Question 18

Which is NOT a part of a step in the XOR operation of encryption method.

A)Convert message text to ASCII
B)Convert ASCII to binary
C)XOR binary numbers with a key
D)XOR ASCII with a key

Question 19

The ____________ cipher is a very old encryption method used by ancient Romans.

Question 20

Which is a widely used public key system that is considered by many experts to be very secure and is available as a plug-in for Netscape Messenger,MSN Messenger,and other communication software?

A)AES
B)Blowfish
C)IDEA
D)PGP

Question 21

Information about an individual or organizational identity,their public key,and its expiration date is contained in a digital certificate issued by a(n)____________.

Question 22

A(n)____________ is actually data attached to a file or e-mail to provide verification of the identity and\or origin of the file or e-mail.

Question 23

Limiting failed log in attempts minimizes the possibility that attackers will eventually determine a password while using software that repeatedly tries a large range of possibilities in a(n)____________ attack.

Question 24

XOR is a mathematical operation on performed on ____________ numbers that results in the basis for data encryption.

Question 25

A free,non-commercial,symmetric block cipher called ____________ uses a variable-length key ranging from 32 to 448 bits.