ECES CERTIFIED ENCRYPTION SPECIALIST REVIEW
What term below best describes an attack in which the attacker obtains ciphertext
corresponding to a set of plaintexts to use in an attempt to derive the key used? -
Answer -Chosen plaintext
Which attack is like a chosen-plaintext attack, except the attacker can obtain ciphertexts
encrypted under two different keys? - Answer -Related-key Attack
What is a known plaintext attack and uses a linear approximation to describe the
behavior of the block cipher and was invented by Mitsarue Matsui ? - Answer -Linear
Cryptanalysis
From the list below, what term describes a mechanism used to create number streams
with random properties? Examples include Lagged Fibonacci and Mersenne Twister. -
Answer -Pseudo-random number generator (PRNG)
What term from the list below best describes a number whose factors are 1 and itself? -
Answer -Prime
Which term from the list below represents the total number of possible values of keys in
a cryptographic algorithm or other security measure? - Answer -Key space
Which term from the list below represents the entire cryptographic operation i.e. the
algorithm, key, and key management functions? - Answer -Cryptosystem
Which cipher makes use of a 5x5 table containing a keyword or key phrase and
encrypts pairs of letters or digraphs? - Answer -Playfair
Which cipher entails using a rod of a certain length to create/encrypt a message, and
the requiring the message recipient to use an identical sized rod to read/decrypt the
message? - Answer -Scytale
What type of cryptanalysis involves the examination of differences in an input and how
that affects the resultant difference in output? - Answer -Differential cryptanalysis
Which WiFi encryption standard is based on 802.11i and uses AES with CCMP to
provide for enhanced confidentiality, integrity and authentication? - Answer -WPA-2
What are the two types of symmetric encryption? - Answer -Block and Stream
Which of the following is true of hash encryption? - Answer -Accepts a variable length
input and produces a fixed length output
Which of the following is NOT required for a hash? - Answer -Minimum key length
, Which of the following are required for a hash? - Answer -input can be any length and
output has a fixed length, is one-way and collision-free
Which software-based stream cipher uses a lagged Fibonacci generator? - Answer -
FISH
The Advanced Encryption Standard is a subset of which algorithm? - Answer -Rijndael
From the list below, which term is best described as random bits added to a password
hash to help with safeguarding passwords in storage? - Answer -Salt
From the list below, which term is best described as a fixed-size, random stream, that is
added to a block cipher to increase randomness? - Answer -Initialization Vector (IV)
The Feistel Network used in symmetric block encryption entails the splitting of a block of
plaintext prior to the application of respective encryption round and XOR functions.
Which cipher from the list below is an "unbalanced" Feistel cipher (i.e. blocks of
plaintext are split into unequal parts)? - Answer -Skipjack
Which term from the list below best describes a number that only shares the number 1
as a common factor with another? - Answer -Co-Prime
What symmetric cipher was developed for use in the clipper chip? - Answer -Skipjack
What trusted entity associated with certificate management is responsible for issuing,
revoking, and managing digital certificates? - Answer -Certificate Authority
What technique should be used in conjunction with substitution to break up letter/word
frequency and aid in combating frequency analysis attacks? - Answer -Transposition
According to Kerchoff's Principle, a cryptosystem will remain secure so long as which
component of it is not publicly known? - Answer -Key
What term below best describes an attack in which the attacker only has access to the
ciphertext of a message? - Answer -Ciphertext only
From the list below, what term best describes an arbitrary, random or pseudo-random
number used only once in cryptographic communication and is then discarded? -
Answer -Nonce
What is Kerckhoffs's principle? - Answer -Only the key needs to be secret, not the
actual algorithm.
If you are sending an encrypted message to a colleague using symmetric encryption, of
the choices below, which key would you use to encrypt the message, and which key
What term below best describes an attack in which the attacker obtains ciphertext
corresponding to a set of plaintexts to use in an attempt to derive the key used? -
Answer -Chosen plaintext
Which attack is like a chosen-plaintext attack, except the attacker can obtain ciphertexts
encrypted under two different keys? - Answer -Related-key Attack
What is a known plaintext attack and uses a linear approximation to describe the
behavior of the block cipher and was invented by Mitsarue Matsui ? - Answer -Linear
Cryptanalysis
From the list below, what term describes a mechanism used to create number streams
with random properties? Examples include Lagged Fibonacci and Mersenne Twister. -
Answer -Pseudo-random number generator (PRNG)
What term from the list below best describes a number whose factors are 1 and itself? -
Answer -Prime
Which term from the list below represents the total number of possible values of keys in
a cryptographic algorithm or other security measure? - Answer -Key space
Which term from the list below represents the entire cryptographic operation i.e. the
algorithm, key, and key management functions? - Answer -Cryptosystem
Which cipher makes use of a 5x5 table containing a keyword or key phrase and
encrypts pairs of letters or digraphs? - Answer -Playfair
Which cipher entails using a rod of a certain length to create/encrypt a message, and
the requiring the message recipient to use an identical sized rod to read/decrypt the
message? - Answer -Scytale
What type of cryptanalysis involves the examination of differences in an input and how
that affects the resultant difference in output? - Answer -Differential cryptanalysis
Which WiFi encryption standard is based on 802.11i and uses AES with CCMP to
provide for enhanced confidentiality, integrity and authentication? - Answer -WPA-2
What are the two types of symmetric encryption? - Answer -Block and Stream
Which of the following is true of hash encryption? - Answer -Accepts a variable length
input and produces a fixed length output
Which of the following is NOT required for a hash? - Answer -Minimum key length
, Which of the following are required for a hash? - Answer -input can be any length and
output has a fixed length, is one-way and collision-free
Which software-based stream cipher uses a lagged Fibonacci generator? - Answer -
FISH
The Advanced Encryption Standard is a subset of which algorithm? - Answer -Rijndael
From the list below, which term is best described as random bits added to a password
hash to help with safeguarding passwords in storage? - Answer -Salt
From the list below, which term is best described as a fixed-size, random stream, that is
added to a block cipher to increase randomness? - Answer -Initialization Vector (IV)
The Feistel Network used in symmetric block encryption entails the splitting of a block of
plaintext prior to the application of respective encryption round and XOR functions.
Which cipher from the list below is an "unbalanced" Feistel cipher (i.e. blocks of
plaintext are split into unequal parts)? - Answer -Skipjack
Which term from the list below best describes a number that only shares the number 1
as a common factor with another? - Answer -Co-Prime
What symmetric cipher was developed for use in the clipper chip? - Answer -Skipjack
What trusted entity associated with certificate management is responsible for issuing,
revoking, and managing digital certificates? - Answer -Certificate Authority
What technique should be used in conjunction with substitution to break up letter/word
frequency and aid in combating frequency analysis attacks? - Answer -Transposition
According to Kerchoff's Principle, a cryptosystem will remain secure so long as which
component of it is not publicly known? - Answer -Key
What term below best describes an attack in which the attacker only has access to the
ciphertext of a message? - Answer -Ciphertext only
From the list below, what term best describes an arbitrary, random or pseudo-random
number used only once in cryptographic communication and is then discarded? -
Answer -Nonce
What is Kerckhoffs's principle? - Answer -Only the key needs to be secret, not the
actual algorithm.
If you are sending an encrypted message to a colleague using symmetric encryption, of
the choices below, which key would you use to encrypt the message, and which key
